Author: "Monica Sigovan" / Topic: medicine - Searchworks@Jio Institute Digital Library Search Results

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1. Hybrid Nano-GdF3 contrast media allows pre-clinical in vivo element-specific K-edge imaging and quantification

Author: Niki Halttunen, Frederic Lerouge, Frederic Chaput, Marc Vandamme, Szilvia Karpati, Salim Si-Mohamed, Monica Sigovan, Loic Boussel, Emmanuel Chereul, Philippe Douek, and Stephane Parola
Subjects: Medicine, Science
Abstract: Abstract Computed tomography (CT) is a widely used imaging modality. Among the recent technical improvements to increase the range of detection for optimized diagnostic, new devices such as dual energy CT allow elemental discrimination but still remain limited to two energies. Spectral photon-counting CT (SPCCT) is an emerging X-ray imaging technology with a completely new multiple energy detection and high spatial resolution (200 μm). This unique technique allows detection and quantification of a given element thanks to an element-specific increase in X-ray absorption for an energy (K-band) depending on its atomic number. The main contrast media used hitherto are iodine-based compounds but the K-edge of iodine (33.2 keV) is out of the range of detection. Therefore, it is crucial to develop contrast media suitable for this advanced technology. Gadolinium, well known and used element for MRI, possess a K-edge (50.2 keV) well suited for the SPCCT modality. The use of nano-objects instead of molecular entities is pushed by the necessity of high local concentration. In this work, nano-GdF3 is validated on a clinical based prototype, to be used as efficient in vivo contrast media. Beside an extremely high stability, it presents long lasting time in the blood pool allowing perfusion imaging of small animals, without apparent toxicity.
Published: 2019
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2. Multicolor spectral photon-counting computed tomography: in vivo dual contrast imaging with a high count rate scanner

Author: David P. Cormode, Salim Si-Mohamed, Daniel Bar-Ness, Monica Sigovan, Pratap C. Naha, Joelle Balegamire, Franck Lavenne, Philippe Coulon, Ewald Roessl, Matthias Bartels, Michal Rokni, Ira Blevis, Loic Boussel, and Philippe Douek
Subjects: Medicine, Science
Abstract: Abstract A new prototype spectral photon-counting computed tomography (SPCCT) based on a modified clinical CT system has been developed. SPCCT analysis of the energy composition of the transmitted x-ray spectrum potentially allows simultaneous dual contrast agent imaging, however, this has not yet been demonstrated with such a system. We investigated the feasibility of using this system to distinguish gold nanoparticles (AuNP) and an iodinated contrast agent. The contrast agents and calcium phosphate were imaged in phantoms. Conventional CT, gold K-edge, iodine and water images were produced and demonstrated accurate discrimination and quantification of gold and iodine concentrations in a phantom containing mixtures of the contrast agents. In vivo experiments were performed using New Zealand White rabbits at several times points after injections of AuNP and iodinated contrast agents. We found that the contrast material maps clearly differentiated the distributions of gold and iodine in the tissues allowing quantification of the contrast agents’ concentrations, which matched their expected pharmacokinetics. Furthermore, rapid, repetitive scanning was done, which allowed measurement of contrast agent kinetics with high temporal resolution. In conclusion, a clinical scale, high count rate SPCCT system is able to discriminate gold and iodine contrast media in different organs in vivo.
Published: 2017
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3. Low WSS Induces Intimal Thickening, while Large WSS Variation and Inflammation Induce Medial Thinning, in an Animal Model of Atherosclerosis.

Author: Antoine Millon, Monica Sigovan, Loic Boussel, Jean-Louis Mathevet, Vanessa Louzier, Christian Paquet, Alain Geloen, Nicolas Provost, Zouher Majd, David Patsouris, Andre Serusclat, and Emmanuelle Canet-Soulas
Subjects: Medicine, Science
Abstract: Atherosclerotic plaque development in the arterial wall is the result of complex interaction between the wall's endothelial layer and blood hemodynamics. However, the interaction between hemodynamic parameters and inflammation in plaque evolution is not yet fully understood. The aim of the present study was to investigate the relation between wall shear stress (WSS) and vessel wall inflammation during atherosclerotic plaque development in a minipig model of carotid stenosis.A surgical procedure was performed to create left common carotid artery stenosis by placement of a perivascular cuff in minipigs under atherogenic diet. Animals were followed up on 3T MRI, 1 week after surgery and 3, 6, and 8 months after initiation of the diet. Computational fluid dynamics simulation estimated WSS distribution for the first imaging point. Vascular geometries were co-registered for direct comparison of plaque development and features (Gadolinium- and USPIO-Contrast Enhanced MRI, for permeability and inflammation respectively) with the initial WSS. Histological analysis was performed and sections were matched to MR images, based on spatial landmarks.Vessel wall thickening, permeability and inflammation were observed distally from the stenosis. They were eccentric and facing regions of normal wall thickness. Histological analysis confirmed eccentric plaque formation with lipid infiltration, intimal thickening and medial degradation. High phagocytic activity in the stenosis region was co-localized with high WSS, corresponding to intense medial degradation observed on histology samples.Lower WSS promotes atherosclerotic plaque development distal to an induced stenosis. Vascular and perivascular inflammation locations were predominant in the high WSS stenosis segment, where medial thinning was the major consequence.
Published: 2015
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4. Feasibility of human vascular imaging of the neck with a large field-of-view spectral photon-counting CT system

Author: Monica Sigovan, Riham Dessouky, Sara Boccalini, Philippe Douek, Loic Boussel, and Salim Si-Mohamed
Subjects: Photons, Large field of view, Vascular imaging, Radiological and Ultrasound Technology, medicine.diagnostic_test, Phantoms, Imaging, business.industry, Imaging diagnostic, Contrast Media, Pilot Projects, General Medicine, Photon counting, Iopamidol, Carotid Arteries, Linear Models, Feasibility Studies, Humans, Medicine, Radiology, Nuclear Medicine and imaging, Tomography, X-Ray Computed, business, Nuclear medicine, Neck, Computed tomography angiography
Published: 2021
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5. Multifocal arterial wall contrast – enhancement in ischemic stroke: A mirror of systemic inflammatory response in acute stroke

Author: Laura Mechtouff, T.-H. Cho, Lise-Prune Berner, Monica Sigovan, Omer Eker, Norbert Nighoghossian, Roxana Ameli, Yves Berthezène, M. Hermier, and Hospices Civils de Lyon (HCL)
Subjects: Male, Middle Cerebral Artery, medicine.medical_specialty, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Gadolinium, Contrast Media, chemistry.chemical_element, Single Center, Asymptomatic, Culprit, 03 medical and health sciences, 0302 clinical medicine, Internal medicine, medicine.artery, medicine, Humans, Carotid Stenosis, 030212 general & internal medicine, Stage (cooking), Stroke, ComputingMilieux_MISCELLANEOUS, Aged, Ischemic Stroke, Aged, 80 and over, business.industry, Brain, Arteries, Middle Aged, Image Enhancement, Intracranial Arteriosclerosis, medicine.disease, Plaque, Atherosclerotic, Systemic Inflammatory Response Syndrome, Neurology, chemistry, Ischemic stroke, Middle cerebral artery, Cardiology, Female, Neurology (clinical), medicine.symptom, business, Carotid Artery, Internal, Magnetic Resonance Angiography, 030217 neurology & neurosurgery
Abstract: Purpose Intracranial plaque gadolinium enhancement revealed by high-resolution MRI imaging (HR MRI) is considered as a marker of plaque inflammation, a contributing factor of plaque unstability. The aim of the present study was to assess the distribution of gadolinium enhancement in intracranial atherosclerosis. Methods Single center analysis of ischemic stroke patients with intracranial atherosclerotic stenosis of M1 or M2 segments of middle cerebral artery, or terminal internal carotid artery (ICA) based on CT-angio or MR-angio. High-resolution MRI imaging (HRMRI) was performed within 6 first weeks following the index event, with 3DT2 BB (black-blood) and 3D T1 BB MR sequences pre and post-contrast administration. Results We identified 8 patients with 14 plaques, 4 were deemed non-culprit and 10 culprit. All culprit plaques (10/10 plaques) and 3 out of 4 non-culprit plaques showed a gadolinium enhancement. Conclusion At the acute/subacute stage of stroke, a gadolinium enhancement may affect multiple asymptomatic intracranial plaques and may reflect a global inflammatory state.
Published: 2020
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6. Feasibility of lung imaging with a large field-of-view spectral photon-counting CT system

Author: Philippe Coulon, Thomas Broussaud, Pierre-Antoine Rodesch, Monica Sigovan, Philippe Douek, D. Gamondes, Elias Lahoud, Sara Boccalini, Salim Si-Mohamed, Riham Dessouky, Loic Boussel, and Yoad Yagil
Subjects: Image quality, Field of view, Iterative reconstruction, Radiation Dosage, Imaging phantom, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Optical transfer function, Image noise, Image Processing, Computer-Assisted, Idose, Medicine, Humans, Radiology, Nuclear Medicine and imaging, Lung, Radiological and Ultrasound Technology, business.industry, Phantoms, Imaging, General Medicine, Photon counting, chemistry, 030220 oncology & carcinogenesis, Feasibility Studies, Radiographic Image Interpretation, Computer-Assisted, Nuclear medicine, business, Tomography, X-Ray Computed, Algorithms
Abstract: Purpose The purpose of this study was to characterize the technical capabilities and feasibility of a large field-of-view clinical spectral photon-counting computed tomography (SPCCT) prototype for high-resolution (HR) lung imaging. Materials and methods Measurement of modulation transfer function (MTF) and acquisition of a line pairs phantom were performed. An anthropomorphic lung nodule phantom was scanned with standard (120 kVp, 62 mAs), low (120 kVp, 11 mAs), and ultra-low (80 kVp, 3 mAs) radiation doses. A human volunteer underwent standard (120 kVp, 63 mAs) and low (120 kVp, 11 mAs) dose scans after approval by the ethics committee. HR images were reconstructed with 1024 matrix, 300 mm field of view and 0.25 mm slice thickness using a filtered-back projection (FBP) and two levels of iterative reconstruction (iDose 5 and 9). The conspicuity and sharpness of various lung structures (distal airways, vessels, fissures and proximal bronchial wall), image noise, and overall image quality were independently analyzed by three radiologists and compared to a previous HR lung CT examination of the same volunteer performed with a conventional CT equipped with energy integrating detectors (120 kVp, 10 mAs, FBP). Results Ten percent MTF was measured at 22.3 lp/cm with a cut-off at 31 lp/cm. Up to 28 lp/cm were depicted. While mixed and solid nodules were easily depicted on standard and low-dose phantom images, higher iDose levels and slice thicknesses (1 mm) were needed to visualize ground-glass components on ultra-low-dose images. Standard dose SPCCT images of in vivo lung structures were of greater conspicuity and sharpness, with greater overall image quality, and similar image noise (despite a flux reduction of 23%) to conventional CT images. Low-dose SPCCT images were of greater or similar conspicuity and sharpness, similar overall image quality, and lower but acceptable image noise (despite a flux reduction of 89%). Conclusions A large field-of-view SPCCT prototype demonstrates HR technical capabilities and high image quality for high resolution lung CT in human.
Published: 2021
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7. Review of an initial experience with an experimental spectral photon-counting computed tomography system

Author: Monica Sigovan, Loic Boussel, Gabrielle Normand, Salim Si-Mohamed, Daniel Bar-Ness, Philippe Douek, Philippe Coulon, Emmanuel Coche, David P. Cormode, and Alain Vlassenbroek
Subjects: Physics, Nuclear and High Energy Physics, medicine.medical_specialty, medicine.diagnostic_test, business.industry, Dual-Energy Computed Tomography, Noise (electronics), Photon counting, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Optics, Contrast-to-noise ratio, Positron emission tomography, 030220 oncology & carcinogenesis, Imaging technology, Medical imaging, medicine, Medical physics, business, Instrumentation, Image resolution
Abstract: Spectral photon-counting CT (SPCCT) is an emerging X-ray imaging technology that extends the scope of available diagnostic imaging tools. The main advantage of photon-counting CT technology is better sampling of the spectral information from the transmitted spectrum in order to benefit from additional physical information being produced during matter interaction, including photo-electric and Compton effects, and the K-edge effect. The K-edge, which is specific for a given element, is the increase in X-ray absorption of the element above the binding energy between its inner electronic shell and the nucleus. Hence, the spectral information contributes to better characterization of tissues and materials of interest, explaining the excitement surrounding this area of X-ray imaging. Other improvements of SPCCT compared with conventional CT, such as higher spatial resolution, lower radiation exposure and lower noise are also expected to provide benefits for diagnostic imaging. In this review, we describe multi-energy CT imaging, from dual energy to photon counting technology, and our initial experience results using a clinical-scale spectral photon counting CT (SPCCT) prototype system in vitro and in vivo. In addition, possible clinical applications are introduced.
Published: 2017
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8. 3D black blood MR angiography of the carotid arteries. A simple sequence for plaque hemorrhage and stenosis evaluation

Author: Philip M. Robson, Zahi A. Fayad, Clément Bidet, Laura Mechtouff, Monica Sigovan, Sébastien Bros, Philippe Douek, Antoine Millon, Loic Boussel, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Service de Radiologie et IRM, Hospices Civils de Lyon, Hospices Civils de Lyon (HCL), Service de neurologie C [Hôpital Pierre Wertheimer - HCL], Hôpital neurologique et neurochirurgical Pierre Wertheimer [CHU - HCL], Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Department of Radiology and Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA., Icahn School of Medicine at Mount Sinai [New York] (MSSM), Département de chirurgie vasculaire, 1 - Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales ( MOTIVATE ), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé ( CREATIS ), Hospices Civils de Lyon ( HCL ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Hospices Civils de Lyon ( HCL ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ), Hospices Civils de Lyon ( HCL ), Service de neurologie C, Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Hospices Civils de Lyon ( HCL ) -Hôpital neurologique et neurochirurgical Pierre Wertheimer [CHU - HCL], and Icahn School of Medicine at Mount Sinai [New York]
Subjects: Male, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, animal diseases, Carotid arteries, Contrast Media, Plaque, Amyloid, Constriction, Pathologic, Intraplaque hemorrhage, 030218 nuclear medicine & medical imaging, 0302 clinical medicine, Image Processing, Computer-Assisted, Medicine, [ SDV.IB.IMA ] Life Sciences [q-bio]/Bioengineering/Imaging, Observer Variation, medicine.diagnostic_test, Middle Aged, Magnetic Resonance Imaging, Plaque, Atherosclerotic, Carotid Arteries, Female, Radiology, Artifacts, Adult, medicine.medical_specialty, Black blood, Biomedical Engineering, Biophysics, Color, Hemorrhage, Sensitivity and Specificity, Article, 03 medical and health sciences, Imaging, Three-Dimensional, Carotid stenosis, Humans, Radiology, Nuclear Medicine and imaging, Aged, Sequence (medicine), Models, Statistical, business.industry, Mr angiography, Reproducibility of Results, Atherosclerosis, medicine.disease, nervous system diseases, Stenosis, 3D MRI, Angiography, business, Magnetic Resonance Angiography, 030217 neurology & neurosurgery
Abstract: International audience; ObjectivesTo evaluate the diagnostic performance of a new three-dimensional T1-weighted turbo-spin-echo sequence (3D T1-w TSE) compared to 3D contrast-enhanced angiography (CE-MRA) for stenosis measurement and compared to 2D T1-w TSE for intra-plaque hemorrhage (IPH) detection.MethodsEighty three patients underwent carotid MRI, using a new elliptic-centric phase encoding T1-weighted 3D TSE sequence in addition to the clinical protocol.Two observers evaluated image quality, presence of flow artifacts, and presence of intra-plaque hemorrhage, and computed the NASCET degree of stenosis for CE-MRA and for the new sequence. Inter-observer agreement and correlation between 3D TSE and CE-MRA for NASCET stenosis was estimated using Cohen's kappa, and correlation using linear regression and Bland-Altman plots.Histology was performed on endarterectomy samples for 18 patients. Sensitivity and specificity of 2D and 3D TSE for IPH diagnosis were computed.Results3D TSE showed better image quality than 2D TSE (p
Published: 2017
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9. Simultaneous assessment of microcalcifications and morphological criteria of vulnerability in carotid artery plaque using hybrid 18F-NaF PET/MRI

Author: Alexandre Paccalet, Laura Mechtouff, Emmanuelle Canet-Soulas, Nicolas Costes, Stephane Luong, Antoine Millon, Yves Berthezène, Patrick Feugier, Thomas Bochaton, Salim Si-Mohamed, Claire Crola Da Silva, Alexandre Bani-Sadr, Didier Le Bars, Norbert Nighoghossian, Monica Sigovan, Diane Collet-Benzaquen, David Magne, Adeline Mansuy, Julie Haesebaert, Philippe Douek, Jérémie Tordo, and Hospices Civils de Lyon, Departement de Neurologie (HCL)
Subjects: medicine.diagnostic_test, business.industry, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Magnetic resonance imaging, [SDV.IB.MN]Life Sciences [q-bio]/Bioengineering/Nuclear medicine, 030204 cardiovascular system & hematology, medicine.disease, Asymptomatic, Culprit, 030218 nuclear medicine & medical imaging, body regions, 03 medical and health sciences, Stenosis, 0302 clinical medicine, Carotid artery plaque, medicine, Mineral metabolism, Radiology, Nuclear Medicine and imaging, Tomography, medicine.symptom, Cardiology and Cardiovascular Medicine, business, Nuclear medicine, Stroke, ComputingMilieux_MISCELLANEOUS
Abstract: Previous studies have suggested the role of microcalcifications in plaque vulnerability. This exploratory study sought to assess the potential of hybrid positron-emission tomography (PET)/magnetic resonance imaging (MRI) using 18F-sodium fluoride (18F-NaF) to check simultaneously 18F-NaF uptake, a marker of microcalcifications, and morphological criteria of vulnerability. We included 12 patients with either recently symptomatic or asymptomatic carotid stenosis. All patients underwent 18F-NaF PET/MRI. 18F-NaF target-to-background ratio (TBR) was measured in culprit and nonculprit (including contralateral plaques of symptomatic patients) plaques as well as in other arterial walls. Morphological criteria of vulnerability were assessed on MRI. Mineral metabolism markers were also collected. 18F-NaF uptake was higher in culprit compared to nonculprit plaques (median TBR 2.6 [2.2-2.8] vs 1.7 [1.3-2.2]; P = 0.03) but was not associated with morphological criteria of vulnerability on MRI. We found a positive correlation between 18F-NaF uptake and calcium plaque volume and ratio but not with circulating tissue-nonspecific alkaline phosphatase (TNAP) activity and inorganic pyrophosphate (PPi) levels. 18F-NaF uptake in the other arterial walls did not differ between symptomatic and asymptomatic patients. 18F-NaF PET/MRI may be a promising tool for providing additional insights into the plaque vulnerability.
Published: 2020
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10. Spectral Photon-Counting Computed Tomography for Coronary Stent Imaging: Evaluation of the Potential Clinical Impact for the Delineation of In-Stent Restenosis

Author: Philippe Douek, Gregor Pahn, Salim Si-Mohamed, David Maintz, Alexander C. Bunck, Grischa Bratke, Monica Sigovan, Daniel Bar-Ness, Tilman Hickethier, and Philippe Coulon
Subjects: medicine.medical_specialty, Computed Tomography Angiography, medicine.medical_treatment, Computed tomography, In Vitro Techniques, Coronary Angiography, 030218 nuclear medicine & medical imaging, Coronary Restenosis, 03 medical and health sciences, 0302 clinical medicine, Restenosis, Coronary stent, medicine, Image Processing, Computer-Assisted, Radiology, Nuclear Medicine and imaging, Photons, medicine.diagnostic_test, business.industry, Phantoms, Imaging, General Medicine, equipment and supplies, medicine.disease, Coronary computed tomography, Photon counting, 3. Good health, Angiography, Stents, Radiology, In stent restenosis, business, Artifacts, 030217 neurology & neurosurgery
Abstract: In-stent restenosis (ISR) is one of the main long-term complications after coronary stent placement, and the ability to evaluate ISR noninvasively using coronary computed tomography (CT) angiography remains challenging. For this application, spectral photon-counting CT (SPCCT) has the potential to increase image quality and reduce artifacts due to its advanced detector technology.Our study aimed to verify the technical and clinical potential of a novel SPCCT prototype using an ISR phantom setup.Soft plaque-like restenosis (45 HU; approximately 50% of the stent lumen) were inserted into 10 different coronary stents (3 mm diameter), which were placed in a vessel phantom and filled with a contrast agent (400 HU). A research prototype SPCCT and a clinical dual-layer CT (DLCT; IQon; Philips) with comparable acquisition and reconstruction parameters were used to scan the phantoms. Conventional polyenergetic (PolyE) and monoenergetic (MonoE) images with 4 different energy levels (40, 60, 90, 120 keV) were reconstructed. Qualitative (delineation of the stenosis and adjacent residual lumen using a 5-point Likert scale) and quantitative (image noise, visible lumen diameter, lumen diameter adjacent to the stenosis, contrast-to-noise ratio of the restenosis) parameters were evaluated for both systems.The qualitative results averaged over all reconstructions were significantly superior for SPCCT compared with DLCT (eg, subjective rating of the best reconstruction of each scanner: DLCT PolyE: 2.80 ± 0.42 vs SPCCT MonoE 40 keV: 4.25 ± 1.03). Stenosis could be clearly detected in 9 and suspected in 10 of the 10 stents with both SPCCT and DLCT. The residual lumen next to the stenosis was clearly delineable in 7 of 10 stents (0.64 ± 0.11 mm or 34.97% of the measured stent lumen) with SPCCT, while it was not possible to delineate the residual lumen for all stents using DLCT. The measured diameter of the lumen within the stent was significantly higher for SPCCT compared with DLCT in all reconstructions with the best results for the MonoE 40 keV images (SPCCT: 1.80 ± 0.17 mm; DLCT: 1.50 ± 0.31 mm). The image noise and the contrast-to-noise ratio were better for DLCT than for SPCCT (contrast-to-noise ratio: DLCT MonoE 40: 31.58 ± 12.54; SPCCT MonoE 40: 4.64 ± 1.30).Spectral photon-counting CT allowed for the noninvasive evaluation of ISR with reliable results regarding the residual lumen for most tested stents and the clear identification or suspicion of stenosis for all stents. In contrast, the residual lumen could not be detected for a single stent using DLCT.
Published: 2019

11. A Spatiotemporal exploration and 3D modeling of blood flow in healthy carotid artery bifurcation from two modalities: Ultrasound-Doppler and phase contrast MRI

Author: Patrick Clarysse, Badii Hmida, Mohamed Hedi Bedoui, Asma Ben Abdallah, Arij Debbich, Mezri Maatouk, Monica Sigovan, Université de Monastir - University of Monastir (UM), Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Modeling & analysis for medical imaging and Diagnosis (MYRIAD), CEDRIC. Traitement du signal et architectures électroniques (CEDRIC - LAETITIA), Centre d'études et de recherche en informatique et communications (CEDRIC), Ecole Nationale Supérieure d'Informatique pour l'Industrie et l'Entreprise (ENSIIE)-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Ecole Nationale Supérieure d'Informatique pour l'Industrie et l'Entreprise (ENSIIE)-Conservatoire National des Arts et Métiers [CNAM] (CNAM), Hôpital Henri Mondor, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Henri Mondor-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Laboratoire Technologie et Imagerie Médicale [Monastir] (TIM), Faculté de Médecine de Monastir [Tunisie], Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 0301 basic medicine, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Carotid Artery, Common, Hemodynamics, Health Informatics, Computational hemodynamics, 03 medical and health sciences, 0302 clinical medicine, PC-MRI, medicine, Carotid bifurcation, Humans, cardiovascular diseases, Bifurcation, ComputingMilieux_MISCELLANEOUS, Ultrasonography, geography, geography.geographical_feature_category, business.industry, Carotid sinus, Blood flow, 3D modeling, Inlet, Magnetic Resonance Imaging, Computer Science Applications, Normal blood flow, US Doppler, 030104 developmental biology, medicine.anatomical_structure, Mesh generation, cardiovascular system, business, 030217 neurology & neurosurgery, Geology, Blood Flow Velocity, Biomedical engineering
Abstract: In the present study, we investigated the velocity profile over the carotid bifurcation in ten healthy volunteers by combining velocity measurements from two imaging modalities (PC-MRI and US-Doppler) and hemodynamic modeling in order to determine the optimal combination for the most realistic velocity estimation. The workflow includes data acquisition, velocity profile extraction at three sites (CCA, ECA and ICA), the arterial geometrical model reconstruction, a mesh generation and a rheological modeling. The results showed that US-Doppler measurements yielded higher velocity values as compared to PC-MRI (about 26% shift in CCA, 52% in ECA and 53% in ICA). This implies higher simulated velocities based on US-Doppler inlet as compared to simulated velocities based on PC-MRI inlet. Overall, PC-MRI inlet based simulations are closer to measurements than US-Doppler inlet based simulations. Moreover, the measured velocities showed that blood flow keeps a parabolic sectional profile distal from CCA, ECA and ICA, while being quite disturbed in the carotid sinus with a significant decrease in magnitude making this site very prone to atherosclerosis.
Published: 2019
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12. Comparison of free breathing 3D mDIXON with single breath-hold 3D inversion recovery sequences for the assessment of Late Gadolinium Enhancement

Author: Monica Sigovan, Philippe Douek, Salim Si-Mohamed, Sara Boccalini, Riham Dessouky, Vincenzo De Stasio, Thomas Broussaud, Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Sigovan, Monica, Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)
Subjects: Adult, Male, Wilcoxon signed-rank test, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, Contrast Media, Gadolinium, 030204 cardiovascular system & hematology, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, Imaging, Three-Dimensional, 0302 clinical medicine, Image Interpretation, Computer-Assisted, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, High spatial resolution, medicine, Humans, Late gadolinium enhancement, Radiology, Nuclear Medicine and imaging, ComputingMilieux_MISCELLANEOUS, Aged, 3d inversion, medicine.diagnostic_test, business.industry, Magnetic resonance imaging, General Medicine, Single breath, Middle Aged, Image Enhancement, Magnetic Resonance Imaging, Female, business, Nuclear medicine, Free breathing, Kappa
Abstract: To evaluate the technical and diagnostic performance of three dimensional (3D) mDIXON versus 3D inversion recovery (3D VIAB) and 3D spectral presaturation with inversion recovery (3D SPIR) late gadolinium enhancement (LGE) sequences.A total of 78 patients (50 males and 28 females, age 49 ± 18 years) with 1.5 T CMR examination including three different 3D LGE sequences (3D mDIXON, 3D VIAB, and 3D SPIR) were evaluated for technical and diagnostic performance by two readers. Qualitative scores and quantitative signal and contrast-to-noise ratios were compared among sequences. Qualitative comparisons were made using Friedman and Wilcoxon signed rank tests. Quantitative comparisons were made using one way ANOVA. Reader agreements were tested using Cohen's Kappa. Any p-value0.05 was significant.19 out of 78 patients (24 %) were excluded due to poor (grade 4) image quality and 29 patients were excluded due to absence of LGE. For the remaining 30 patients, free breathing 3D mDIXON showed higher confidence in diagnosis of subepicardial LGE (p-value0.05). 3D mDIXON outperformed 3D SPIR in both visualization of LGE (p = 0.02) and quality of fat suppression (p = 0.001). Nevertheless, 3D mDIXON showed lower image quality compared to the other two sequences.Free breathing 3D mDIXON is a diagnostic problem-solving tool, especially when making a diagnosis of subepicardial enhancement and/or fat suppression is needed, owing to its high spatial resolution and robust fat suppression. Choice of 3D LGE sequence should be based on patient's breath-hold ability, diagnostic needs, and institutional availability considering the strengths and limitations of each sequence.
Published: 2021
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13. In vivo demonstration of pulmonary microvascular involvement in COVID-19 using dual-energy computed tomography

Author: Philippe Douek, Monica Sigovan, Loic Boussel, Lea Zumbihl, Salim Si-Mohamed, Sara Boccalini, Jean-François Mornex, Vincent Cottin, Nader Chebib, Ségolène Turquier, Hôpital Louis Pradel [CHU - HCL], Hospices Civils de Lyon (HCL), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Modeling & analysis for medical imaging and Diagnosis (MYRIAD), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Infections Virales et Pathologie Comparée - UMR 754 (IVPC), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre de compétence de l'hypertension pulmonaire sévère, ROSSI, Sabine, Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), and Sigovan, Monica
Subjects: Pulmonary and Respiratory Medicine, Coronavirus disease 2019 (COVID-19), [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, Computed tomography, 030204 cardiovascular system & hematology, [SDV.MHEP.PSR]Life Sciences [q-bio]/Human health and pathology/Pulmonology and respiratory tract, 03 medical and health sciences, 0302 clinical medicine, In vivo, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Medicine, Agora, ComputingMilieux_MISCELLANEOUS, medicine.diagnostic_test, business.industry, Lung perfusion, Dual-Energy Computed Tomography, medicine.disease, Thrombosis, Research Letters, respiratory tract diseases, 3. Good health, Perfusion (blood), 030220 oncology & carcinogenesis, [SDV.MHEP.PSR] Life Sciences [q-bio]/Human health and pathology/Pulmonology and respiratory tract, Tomography, Nuclear medicine, business
Abstract: Vascular involvement in coronavirus disease 2019 (COVID-19) has been suggested by several observations, such as the high rate of pulmonary embolism [1], the prothrombotic state and the proinflammatory biological profile [2, 3], as well as the pathological findings of severe endothelial injury and diffuse thrombosis [4]. Dual-energy computed tomography (DECT) allows specific imaging of the iodinated contrast agent distribution within the lung, which has been demonstrated as a surrogate marker of lung perfusion [5, 6]. Therefore, our goal was to assess in vivo pulmonary microvascular involvement in patients with COVID-19 pneumonia by using DECT and to determine whether vascular changes vary during the course of the disease., In COVID-19 pneumonia, dual-energy computed tomography has shown two patterns of lung perfusion along the course of the disease: an increase in perfusion blood volume (PBV) with ground-glass opacities and a decrease in PBV with consolidation https://bit.ly/2Zh0XcI
Published: 2020
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14. MRI-based detection of renal artery abnormalities related to renal denervation by catheter-based radiofrequency ablation in drug resistant hypertensive patients

Author: Loic Boussel, Brahim Harbaoui, Salim Si-Mohamed, Philippe Douek, Pierre Lantelme, Monica Sigovan, Marc Sapoval, Sébastien Bros, Pierre-Yves Courand, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon, Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Centre Hospitalier Universitaire de Nîmes (CHU Nîmes), Centre de Recherche et d'Application en Traitement de l'Image et du Signal (CREATIS), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université Paris Descartes - Faculté de Médecine (UPD5 Médecine), Université Paris Descartes - Paris 5 (UPD5), Service de Radiologie [CHU HEGP], Hôpital Européen Georges Pompidou [APHP] (HEGP), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpitaux Universitaires Paris Ouest - Hôpitaux Universitaires Île de France Ouest (HUPO)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpitaux Universitaires Paris Ouest - Hôpitaux Universitaires Île de France Ouest (HUPO), Service de radiologie cardio-vasculaire [CHU HEGP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Européen Georges Pompidou [APHP] (HEGP), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpitaux Universitaires Paris Ouest - Hôpitaux Universitaires Île de France Ouest (HUPO)-Hôpitaux Universitaires Paris Ouest - Hôpitaux Universitaires Île de France Ouest (HUPO), Centre Hospitalier Régional Universitaire de Nîmes (CHRU Nîmes), Hôpitaux Universitaires Paris Ouest - Hôpitaux Universitaires Île de France Ouest (HUPO)-Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-Hôpitaux Universitaires Paris Ouest - Hôpitaux Universitaires Île de France Ouest (HUPO)-Assistance publique - Hôpitaux de Paris (AP-HP) (APHP), Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-Hôpital Européen Georges Pompidou [APHP] (HEGP), and Hôpitaux Universitaires Paris Ouest - Hôpitaux Universitaires Île de France Ouest (HUPO)-Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-Hôpitaux Universitaires Paris Ouest - Hôpitaux Universitaires Île de France Ouest (HUPO)
Subjects: Male, medicine.medical_specialty, Radiofrequency ablation, medicine.medical_treatment, [SDV]Life Sciences [q-bio], Drug Resistance, 030204 cardiovascular system & hematology, Imagerie Coeur - Vaisseaux - Poumons, law.invention, Labex PRIMES, 03 medical and health sciences, Renal Artery, 0302 clinical medicine, law, medicine.artery, medicine, Humans, Radiology, Nuclear Medicine and imaging, Prospective Studies, 030212 general & internal medicine, Sympathectomy, Renal artery, Intraoperative Complications, Antihypertensive Agents, ComputingMilieux_MISCELLANEOUS, Aged, Neuroradiology, Denervation, Analysis of Variance, medicine.diagnostic_test, business.industry, categₘed, reseauₐucun, Magnetic resonance imaging, Interventional radiology, General Medicine, Middle Aged, Ablation, Magnetic Resonance Imaging, 3. Good health, Catheter, Imagerie Ultrasonore, Hypertension, Catheter Ablation, Female, [SDV.IB]Life Sciences [q-bio]/Bioengineering, Radiology, business, Nuclear medicine
Abstract: International audience; OBJECTIVES: Endovascular renal denervation (RDN) using catheter-based radiofrequency (RF) ablation has emerged as a potential treatment option for drug-resistant hypertension. Its efficacy is currently under debate. We aimed to evaluate the capability of contrast-enhanced magnetic resonance imaging (MRI) to assess the effects of RDN on the renal arterial wall in patients presenting with drug-resistant hypertension.METHODS: Patients were included prospectively following institutional review board approval and written informed consent. Renal arteries were imaged using a two-dimensional T1-weighted TSE sequence pre- and post-administration of a gadolinium-based contrast agent, before (D0), 2 days (D2) and 6 months (M6) after RDN. Mean enhancement of the wall (mENH) and mean wall thickness (mWT) were compared across time using an ANOVA with repeated measures and post-hoc paired t-test.RESULTS: Follow-up was completed for 23 patients (median age, 57 years; 16 men). The mENH at D2 (96.3 \textpm 36.0 %) was significantly higher than at D0 (61.1 \textpm 26.3%, p < 0.001) and M6 (66.1\textpm22.7%, p < 0.001). Similarly, mWT was significantly higher at D2 (3.1 \textpm 0.4 m) than at D0 (2.7 \textpm 0.4mm, p < 0.001) and M6 (2.9 \textpm 0. 5 mm, p = 0.002).CONCLUSIONS: MRI demonstrated abnormalities of the arterial wall 2 days after RDN that had resolved at 6 months.KEY POINTS: \textbullet Contrast-enhanced MRI provides anatomic evidence of renal artery RF ablation \textbullet Temperature increase related to RF ablation induces transient arterial wall inflammation \textbullet Morphological effects observed 2 days post RF ablation are not visible after 6 months.
Published: 2018
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15. What's Behind a '+' Sign? Perceiving an Arithmetic Operator Recruits Brain Circuits for Spatial Orienting

Author: Anne Cheylus, Michel Fayol, Monica Sigovan, Audrey Breton, Catherine Thevenot, Romain Mathieu, Jérôme Prado, Justine Epinat-Duclos, Université de Genève = University of Geneva (UNIGE), Institut des Sciences cognitives Marc Jeannerod - Laboratoire sur le langage, le cerveau et la cognition (L2C2), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Psychologie Sociale et Cognitive (LAPSCO), Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Université de Lausanne = University of Lausanne (UNIL), Université de Genève (UNIGE), École normale supérieure - Lyon (ENS Lyon)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), University of Lausanne (UNIL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), LAPSCO, HAL, Faculté de Psychologie et des Sciences de l’Education, Institut des Sciences Cognitives (ISC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Laboratoire de psychologie sociale et de psychologie cognitive (LAPSCO), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), institut de psychologie, université de Lausanne, Université de Genève ( UNIGE ), Institut des Sciences Cognitives ( ISC ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique ( CNRS ), 1 - Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales ( MOTIVATE ), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé ( CREATIS ), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Hospices Civils de Lyon ( HCL ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Hospices Civils de Lyon ( HCL ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de psychologie sociale et de psychologie cognitive ( LAPSCO ), Université Blaise Pascal - Clermont-Ferrand 2 ( UBP ) -Centre National de la Recherche Scientifique ( CNRS ), and Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)
Subjects: Adult, Male, Adolescent, Computer science, Cognitive Neuroscience, media_common.quotation_subject, Rote learning, Space, Cognitive neuroscience, Functional Laterality, 050105 experimental psychology, Arabic numerals, [ SDV.NEU.SC ] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences, Young Adult, 03 medical and health sciences, Cellular and Molecular Neuroscience, 0302 clinical medicine, Symbol, Neural Pathways, Image Processing, Computer-Assisted, medicine, Humans, 0501 psychology and cognitive sciences, Attention, Arithmetic, media_common, Brain Mapping, medicine.diagnostic_test, 05 social sciences, Operator (linguistics), fMRI, Brain, [SDV.NEU.SC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences, Magnetic Resonance Imaging, Degree (music), Oxygen, Pattern Recognition, Visual, Space Perception, [SCCO.PSYC] Cognitive science/Psychology, [SCCO.PSYC]Cognitive science/Psychology, Female, Functional magnetic resonance imaging, Mathematics, [SDV.NEU.SC] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences, 030217 neurology & neurosurgery, Sign (mathematics)
Abstract: International audience; Do mathematical symbols evoke spatial representations? Although behavioral studies have long demonstrated interactions between space and the processing of Arabic digits, how to interpret these results remains controversial. Here, we tested whether activity in regions supporting spatial processing contributes to the processing of symbols conveying fundamental arithmetic concepts-such as operation signs-even in the absence of associated digits. Using functional magnetic resonance imaging, we show that merely perceiving a "+" sign triggers activity in brain regions that support the orienting of spatial attention in adults. Activity in these regions was greater for "+" than for "x" signs, indicating that it is modulated by whether an operator reflects an operation that evokes numerical manipulation (rather than rote memorization). Finally, the degree to which subjects activated a spatial region in response to a "+" sign was correlated with the degree to which subjects benefited from being briefly presented with that sign before having to calculate a single-digit addition problem, an effect termed operator-priming. Therefore, not only are some arithmetic operators linked to spatial intuitions, but such intuitions might also have an important role during arithmetic calculation. More generally, our findings support the view that mathematical symbols inherently evoke spatial representations.
Published: 2018
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16. MR imaging assessment of myocardial edema with T2 mapping

Author: Didier Revel, Patrick Montant, Monica Sigovan, Philippe Douek, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Department of Radiology, Cardiological Hospital, and Hospices Civils de Lyon
Subjects: medicine.medical_specialty, Cardiac magnetic resonance, Biopsy, T2 mapping, Myocardial edema, computer.software_genre, Sensitivity and Specificity, Voxel, Edema, Image Interpretation, Computer-Assisted, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Humans, Medicine, Radiology, Nuclear Medicine and imaging, Cardiac imaging, Radiological and Ultrasound Technology, business.industry, Myocardium, Heart, General Medicine, Magnetic Resonance Imaging, Mr imaging, T2 relaxation, cardiovascular system, Radiology, medicine.symptom, Cardiomyopathies, business, Nuclear medicine, computer, Endocardium
Abstract: Cardiac magnetic resonance (CMR) provides a high signal-to-noise ratio, high spatial and temporal resolutions, as well as a delayed-enhancement sequence and is therefore considered a reference technique in the field of cardiac imaging. However, currently available sequences are not adequate to assess some pathologic conditions, such as myocardial edema. T2 mapping sequences generate parametric images that are based on the transverse relaxation time (T2) for each voxel. In case of edema, the T2 relaxation time is longer. This review summarizes current knowledge on CMR T2 mapping for assessing myocardial edema.
Published: 2015
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17. Extended 3D approach for quantification of abnormal ascending aortic flow

Author: Monica Sigovan, Elaine E. Tseng, Jarrett Wrenn, Petter Dyverfeldt, David Saloner, and Michael D. Hope
Subjects: Adult, Heart Defects, Congenital, Male, Aortic valve, medicine.medical_specialty, Heart Valve Diseases, Biomedical Engineering, Biophysics, Article, Imaging, Three-Dimensional, Bicuspid Aortic Valve Disease, Internal medicine, medicine.artery, Ascending aorta, medicine, Humans, Eccentric, Radiology, Nuclear Medicine and imaging, Displacement (orthopedic surgery), Aorta, Aged, medicine.diagnostic_test, business.industry, Magnetic resonance imaging, Aortic Valve Stenosis, Middle Aged, medicine.disease, Magnetic Resonance Imaging, medicine.anatomical_structure, Flow (mathematics), Aortic Valve, Aortic valve stenosis, cardiovascular system, Cardiology, Female, business, Blood Flow Velocity
Abstract: Flow displacement quantifies eccentric flow, a potential risk factor for aneurysms in the ascending aorta, but only at a single anatomic location. The aim of this study is to extend flow displacement analysis to 3D in patients with aortic and aortic valve pathologies.43 individuals were studied with 4DFlow MRI in 6 groups: healthy, tricuspid aortic valve (TAV) with aortic stenosis (AS) but no dilatation, TAV with dilatation but no AS, and TAV with both AS and dilatation, BAV without AS or dilatation, BAV without AS but with dilation. The protocol was approved by our institutional review board, and informed consent was obtained. Flow displacement was calculated for multiple planes along the ascending aorta, and 2D and 3D analyses were compared.Good correlation was found between 2D flow displacement and both maximum and average 3D values (r0.8). Healthy controls had significantly lower flow displacement values with all approaches (p0.05). The highest flow displacement was seen with stenotic TAV and aortic dilation (0.24±0.02 with maximum flow displacement). The 2D approach underestimated the maximum flow displacement by more than 20% in 13 out of 36 patients (36%).The extended 3D flow displacement analysis offers a more comprehensive quantitative evaluation of abnormal systolic flow in the ascending aorta than 2D analysis. Differences between patient subgroups are better demonstrated, and maximum flow displacement is more reliably assessed.
Published: 2015
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18. 18 F-NaF PET-MRI: an innovative tool to assess carotid artery plaque vulnerability

Author: Laura Mechtouff, N. Costes, Norbert Nighoghossian, Philippe Douek, Yves Berthezène, Monica Sigovan, D. Collet‐Benzaquen, Stroke Department, Neurological Hospital, Hospices Civils de Lyon (HCL), Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Etude et de Recherche Multimodal Et Pluridisciplinaire en imagerie du vivant (CERMEP - imagerie du vivant), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-CHU Grenoble-Hospices Civils de Lyon (HCL)-CHU Saint-Etienne-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Department of Radiology, Cardiological Hospital, Hospices Civils de Lyon, Laboratoire Technipath, Neuroradiology Department, Neurological Hospital, and ANR-10-IBHU-0003,CESAME,Institut Cerveau et Santé Mentale(2010)
Subjects: 0301 basic medicine, business.industry, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Vulnerability, 03 medical and health sciences, chemistry.chemical_compound, 030104 developmental biology, Carotid artery plaque, positron emission tomography computed tomography, Neurology, chemistry, Sodium fluoride, sodium fluoride, Medicine, carotid stenosis, Neurology (clinical), business, Nuclear medicine, ComputingMilieux_MISCELLANEOUS, Positron Emission Tomography-Computed Tomography
Abstract: International audience
Published: 2018
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19. Benign and malignant enlarged chest nodes staging by diffusion-weighted MRI: an alternative to mediastinoscopy?

Author: Pia Akl, Caroline Mesmann, Salim Si-Mohamed, Loic Boussel, Philippe Douek, Monica Sigovan, François Tronc, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Service de Radiologie [Hôpital de la Croix-Rousse - HCL], Hôpital de la Croix-Rousse [CHU - HCL], Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Service de chirurgie thoracique (HCL, Hôpital Louis Pradel, Bron), Hospices Civils de Lyon (HCL)-Hôpital Louis Pradel [CHU - HCL], Hospices Civils de Lyon (HCL), Service de Radiologie et IRM [CHU Lyon], and Hôpital Cardiovasculaire Louis Pradel (HCLP)
Subjects: Adult, medicine.medical_specialty, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, [SDV.CAN]Life Sciences [q-bio]/Cancer, Sensitivity and Specificity, 030218 nuclear medicine & medical imaging, Mediastinoscopy, 03 medical and health sciences, 0302 clinical medicine, Predictive Value of Tests, medicine, Effective diffusion coefficient, Humans, Radiology, Nuclear Medicine and imaging, Prospective Studies, Aged, Aged, 80 and over, medicine.diagnostic_test, Receiver operating characteristic, Full Paper, business.industry, Mediastinum, General Medicine, Middle Aged, medicine.anatomical_structure, Diffusion Magnetic Resonance Imaging, 030220 oncology & carcinogenesis, Predictive value of tests, Lymphatic Metastasis, Background suppression, Radiology, Lymph Nodes, business, Diffusion MRI
Abstract: International audience; Objective:To evaluate the accuracy of diffusion-weighted MRI with background suppression (DWIBS) in differentiating between malignant and benign mediastinal lymph-nodes.Methods:Consecutive patients with enlarged mediastinal lymph-nodes underwent MRI DWIBS within 10 days prior to mediastinoscopy. Relative contrast ratios (RCRs) were computed on b800 and apparent diffusion coefficient (ADC) maps by dividing the node signal with the chest muscle signal, using manually drawn regions of interest (ROIs) by radiologists, blinded to pathology. Unpaired Student's t-tests were used to compare RCR-b800 and ADC between malignant and benign nodes. Receiver operating characteristic curves analyses were also performed.Results:Six patients were excluded for poor image quality. Analysis was performed for 54 patients. Mean ADC values were significantly higher for benign (1740 ± 401 × 10−6 mm2 s–1) compared with malignant nodes (1266 ± 403 × 10−6 mm2 s–1, p = 0.0001). Mean RCR-b800 values were significantly lower for benign (2.64 ± 1.07) compared with malignant nodes (6.44 ± 3.47, p < 0.0001).Receiver operating characteristic analysis for RCR-b800 (cut-off of 3.6), showed a sensitivity of 90.9%, a specificity 83% and an accuracy 85% for differentiating benign from malignant nodes. For ADC (cut-off of 1285), the sensitivity was 68.2%, the specificity 84.6% and the accuracy 80.4%.Conclusion:DWIBS can accurately differentiate malignant from benign states in enlarged mediastinal lymph-nodes and represents an alternative method in aetiological work-up of mediastinal lymphadenopathies.Advances in knowledge:DWIBS may represent a useful adjunctive imaging modality, particularly for diagnosis of benign mediastinal lymph node, and thus may reduce the frequency of futile mediastinoscopy, which remains an invasive procedure.
Published: 2018
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20. Evaluation of image quality of DWIBS versus DWI sequences in thoracic MRI at 3T

Author: Loic Boussel, Philippe Douek, Adva Abergel, François Tronc, Yves Berthezène, Lise-Prune Berner, Caroline Mesmann, Monica Sigovan, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut d'astrophysique spatiale (IAS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Sud - Paris 11 (UP11), Service de Radiologie [Hôpital de la Croix-Rousse - HCL], Hôpital de la Croix-Rousse [CHU - HCL], Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Imagerie Ultrasonore, Department of Radiology, Cardiological Hospital, Hospices Civils de Lyon, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Adult, Male, medicine.medical_specialty, Image quality, Biomedical Engineering, Biophysics, Fat suppression, 030218 nuclear medicine & medical imaging, Motion, 03 medical and health sciences, 0302 clinical medicine, Image Processing, Computer-Assisted, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, medicine, Humans, Radiology, Nuclear Medicine and imaging, Prospective Studies, Lymph node, Aged, medicine.diagnostic_test, business.industry, Respiration, Mediastinum, Water, Magnetic resonance imaging, Middle Aged, Magnetic Resonance Imaging, Diffusion Magnetic Resonance Imaging, medicine.anatomical_structure, Adipose Tissue, 030220 oncology & carcinogenesis, Mediastinal lymph node, Female, Lymph Nodes, Radiology, Lymph, Artifacts, Nuclear medicine, business, Diffusion MRI
Abstract: To compare diffusion weighted imaging with background suppression (DWIBS) sequence with classic spectral diffusion sequence (DWI) with and without respiratory gating in mediastinal lymph node analysis at 3T.26 patients scheduled for mediastinoscopic lymph node analysis, prospectively undergone a thoracic 3T MRI with DWIBS (FatSat=STIR; TR/TE=6674.1/44.7ms; IR=260 ms) and DWI sequences (FatSat=SPIR; TR/TE=1291/59.6 ms) (b=0-400-800 s/mm2) with and without (free breathing) respiratory gating. Images at b=800 were analyzed by two radiologists. They performed qualitative analysis of fat-sat homogeneity and motion artifacts, rated from 0 to 4, and quantitative evaluation by studying signal to background (STB) of lymph nodes.Quality of fat suppression was significantly higher for DWIBS than for DWI both for free-breathing (score 3.48±0.65 vs. 1.76±0.96, p0.0001) and respiratory-gated scans (3.17±0.77 vs. 1.72±0.73, p=0.0001). Similarly, artifacts were reduced with DWIBS (3.16±0.47 vs. 1.76±0.59, p0.0001; 3.0±0.73 vs. 2.04±0.53, p=0.0001). Quantitative analysis showed higher STB with DWIBS (3.26±1.83 vs. 0.98±0.44, p0.0001; 3.56±, 2.09 vs. 0.92±0.59, p0.0001). Gating did not improve image quality and STB on DWIBS (p0.05).In thoracic MRI, ungated DWIBS sequence improves fat-sat homogeneity, reduces motion artifacts and increases STB of lymph nodes. Respiratory gating does not improve DWIBS image quality.
Published: 2014
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21. MRI hemodynamic markers of progressive bicuspid aortic valve-related aortic disease

Author: S. Jarrett Wrenn, Petter Dyverfeldt, David Saloner, Monica Sigovan, and Michael D. Hope
Subjects: Aortic valve, congenital, hereditary, and neonatal diseases and abnormalities, Aorta, medicine.medical_specialty, medicine.diagnostic_test, business.industry, Disease progression, Hemodynamics, medicine.disease, Aortic disease, Magnetic resonance angiography, medicine.anatomical_structure, Bicuspid aortic valve, medicine.artery, Internal medicine, Cohort, cardiovascular system, Cardiology, Medicine, Radiology, Nuclear Medicine and imaging, cardiovascular diseases, Radiology, business
Abstract: Purpose To determine the reproducibility of MRI aortic hemodynamic markers and to assess their relationship to aortic growth in a cohort of patients with bicuspid aortic valves (BAV).
Published: 2013
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22. Molecular MRI of Atherosclerosis with USPIO

Author: Emmanuelle Canet-Soulas and Monica Sigovan
Subjects: Pathology, medicine.medical_specialty, Histology, Cell adhesion molecule, business.industry, Inflammation, Cell Biology, Applied Microbiology and Biotechnology, In vivo, Toxicity, medicine, Molecular mri, Platelet activation, medicine.symptom, Molecular imaging, business, Preclinical imaging
Abstract: Inflammation in atherosclerosis is a risk factor for plaque rupture and atherothrombosis. USPIO-enhanced MRI is capable of evaluating the inflammatory activity in vivo on a cellular as well as a sub-cellular level. This paper reviews the recent advances in USPIO-enhanced MRI of atherosclerotic plaque inflammation. Imaging strategies for evidentiating the presence of the USPIO label in plaques take advantage of the susceptibility effect induced by the nanoparticles in their surroundings to obtain a negative contrast (T2* weighted imaging) or a positive contrast (the White Maker and Susceptibility Gradient Mapping). Quantitative methods have more recently been adapted to in vivo imaging of USPIO in atherosclerotic plaques, and showed great promise in detecting treatment responses. When they are not taken up rapidly from blood by the reticulo-endothelial system (RES), USPIOs nanoparticles passively target inflammation in atherosclerosis by engulfment in intra-plaque phagocytic cells. This has been demonstrated in both animal models and human patients. However, by modifying the surface of coating materials, nanoparticles can actively target atherosclerosis molecular and cellular actors in animal models. The goal of molecular imaging of atherosclerotic plaques is to identify events in the early onset of the disease, as well as critical evolution to vulnerable plaques. USPIO agents are preferred as basis to develop targeted agents because of the ability to overcome the toxicity issue of long-term body residence of Gd-based agents, and their lower sensitivity based on their relaxivity properties. MRI agents capable of efficiently targeting oxidized LDL, cell adhesion molecules (VCAM-1, P-selectin, E-selection), apoptosis and activated platelets have been demonstrated in animal models. The use of these methodologies at the clinical level will depend on the availability and toxicity profiles of the agents, and will require standardized state of the art imaging techniques.
Published: 2012
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23. Positive contrast with therapeutic iron nanoparticles at 4.7 T

Author: Emmanuelle Canet-Soulas, Monica Sigovan, Delphine Charpigny, Achraf Al Faraj, Hatem Fessi, Misara Hamoudeh, Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Laboratoire d'automatique et de génie des procédés (LAGEP), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Biophysics, Contrast Media, Nanoparticle, Nanotechnology, Sensitivity and Specificity, 030218 nuclear medicine & medical imaging, Mice, 03 medical and health sciences, 0302 clinical medicine, Nuclear magnetic resonance, Image Interpretation, Computer-Assisted, mental disorders, medicine, Animals, Computer Simulation, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Radiology, Nuclear Medicine and imaging, Magnetite Nanoparticles, Radiological and Ultrasound Technology, medicine.diagnostic_test, Phantoms, Imaging, ACL, Tumor therapy, Dextrans, Magnetic resonance imaging, [SDV.SP]Life Sciences [q-bio]/Pharmaceutical sciences, Image enhancement, Image Enhancement, Magnetic Resonance Imaging, Positive contrast, Feasibility Studies, Magnetic nanoparticles, Female, psychological phenomena and processes, 030217 neurology & neurosurgery, Gradient echo, Superparamagnetism
Abstract: The purpose of the study was to show the feasibility of a positive contrast technique GRadient echo Acquisition for Superparamagnetic particles with Positive contrast (GRASP), for a specific type of magnetic particles, designed for tumor treatment under MRI monitoring.A simulation study was performed to estimate field inhomogeneity intensities induced by increasing concentrations of particles at different static fields. The GRASP sequence was setup on a 4.7 T Bruker system during an in vitro study. Six mice, included in the in vivo study received particles in the left calf muscle and contrast enhancement values, were measured over three time points, for both negative and positive contrast images.Comparing values obtained by simulation at 1.5, 3, and 4.7 T, the strongest susceptibility effect was obtained at 4.7 T. Based on simulation and in vitro data, gradient settings were chosen for in vivo imaging. GRASP resulted in bright regions at and around the injection site, and higher enhancement values, compared to standard GRE imaging. Both contrasts were useful for longitudinal follow-up, with a faster decay over time for GRASP.The magnetic nanoparticles for drug delivery can be detected using positive contrast. Combining imaging sequences, i.e., negative contrast and susceptibility methods, increased imaging specificity of large magnetic particles and enabled their follow-up for theranostic applications.
Published: 2011
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24. MRI BASED DETECTION OF RENAL ARTERY ABNORMALITIES RELATED TO RENAL DENERVATION BY CATHETER BASED RADIO-FREQUENCY ABLATION IN DRUG RESISTANT HYPERTENSIVE PATIENTS

Author: S. Si Mohamed, PC Douek, Monica Sigovan, Pierre Lantelme, P.Y. Courand, L. Boussel, Brahim Harbaoui, and Marc Sapoval
Subjects: Denervation, medicine.medical_specialty, Physiology, business.industry, medicine.medical_treatment, Drug resistance, Ablation, Catheter, medicine.artery, Internal medicine, Internal Medicine, medicine, Cardiology, Renal artery, Cardiology and Cardiovascular Medicine, business
Published: 2018
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25. M1-Activated Macrophages Migration, A Marker of Aortic Atheroma Progression

Author: Geneviève De Souza, Monica Sigovan, Emmanuelle Canet-Soulas, Hasan Alsaid, Norbert Nighoghossian, Zouher Majd, Serge Nataf, Amine Bessaad, Christine Ménager, Florence Lagarde, Jérôme Honnorat, Nicolas Provost, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche et d'Application en Traitement de l'Image et du Signal (CREATIS), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de Biologie du Développement de Marseille (IBDM), Aix Marseille Université (AMU)-Collège de France (CdF)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche en neurosciences de Lyon (CRNL), Université de Lyon-Université de Lyon-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique de l'état condensé (LPEC), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM), Sigovan, Monica, Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche en neurosciences de Lyon - Lyon Neuroscience Research Center (CRNL), and Université de Lyon-Université de Lyon-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Aortic arch, Pathology, medicine.medical_specialty, Apolipoprotein E2, Arteriosclerosis, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, Aortic Diseases, Mice, Transgenic, Proinflammatory cytokine, Mice, In vivo, medicine.artery, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, medicine, Animals, Macrophage, Radiology, Nuclear Medicine and imaging, Gene Knock-In Techniques, medicine.diagnostic_test, business.industry, Macrophages, Histology, Magnetic resonance imaging, General Medicine, Macrophage Activation, medicine.disease, Magnetic Resonance Imaging, Atheroma, Dynamic contrast-enhanced MRI, business, Biomarkers
Abstract: Background: M1-activated Macrophages (M1M) play a major role in atherosclerotic lesions of aortic arch, promoting proinflammatory response. In vivo trafficking of M1M in aortic plaques is therefore critical. Methods: M1M from bone marrow cell culture were magnetically labeled, using iron nanoparticles, intravenously injected and followed up with 3 day magnetic resonance imaging (MRI) in mice developing macrophage-laden atheroma (ApoE2 knock-in mice). M1M recruitment in aortic arch lesions was assessed both by MRI and histology. Results: In all ApoE2 knock-in mice injected with labeled cells, high resolution MRI showed localized signal loss regions in the thickened aortic wall, with a maximal effect at day 2 (―34% ± 7.3% P < 0.001 compared with baseline). This was confirmed with Prussian blue (iron) staining and corresponded to M1M (Major Histo-compatibility Complex II positive). Clear different intraplaque and adventitial dynamic distribution profiles of labeled cells were observed during the 3 days. Conclusion: M1M dynamic MRI is a promising marker to noninvasively assess the macrophage trafficking underlying aortic arch plaque progression.
Published: 2010
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26. Low WSS Induces Intimal Thickening, while Large WSS Variation and Inflammation Induce Medial Thinning, in an Animal Model of Atherosclerosis

Author: Emmanuelle Canet-Soulas, Monica Sigovan, Antoine Millon, David Patsouris, Nicolas Provost, Zouher Majd, Vanessa Louzier, André Sérusclat, Jean-Louis Mathevet, Loic Boussel, Christian Paquet, Alain Géloën, Hospices Civils de Lyon (HCL), Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National de la Recherche Agronomique (INRA), Hémostase, Inflammation et sepsis (EA 4609), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS), Hopital Cardio-Thoracique et Vasculaire Louis Pradel, Hôpital Louis Pradel [CHU - HCL], Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL)
Subjects: Vasculitis, Pathology, medicine.medical_specialty, Endothelium, Swine, [SDV]Life Sciences [q-bio], Hypercholesterolemia, lcsh:Medicine, Hemodynamics, Inflammation, Carotid Intima-Media Thickness, medicine, Eccentric, Animals, lcsh:Science, Phagocytes, Multidisciplinary, medicine.diagnostic_test, business.industry, lcsh:R, Magnetic resonance imaging, medicine.disease, Atherosclerosis, Biomechanical Phenomena, Stenosis, medicine.anatomical_structure, Carotid Arteries, Cuff, Angiography, cardiovascular system, Swine, Miniature, lcsh:Q, Endothelium, Vascular, medicine.symptom, business, Research Article
Abstract: International audience; OBJECTIVE: Atherosclerotic plaque development in the arterial wall is the result of complex interaction between the wall's endothelial layer and blood hemodynamics. However, the interaction between hemodynamic parameters and inflammation in plaque evolution is not yet fully understood. The aim of the present study was to investigate the relation between wall shear stress (WSS) and vessel wall inflammation during atherosclerotic plaque development in a minipig model of carotid stenosis. METHODS: A surgical procedure was performed to create left common carotid artery stenosis by placement of a perivascular cuff in minipigs under atherogenic diet. Animals were followed up on 3T MRI, 1 week after surgery and 3, 6, and 8 months after initiation of the diet. Computational fluid dynamics simulation estimated WSS distribution for the first imaging point. Vascular geometries were co-registered for direct comparison of plaque development and features (Gadolinium- and USPIO-Contrast Enhanced MRI, for permeability and inflammation respectively) with the initial WSS. Histological analysis was performed and sections were matched to MR images, based on spatial landmarks. RESULTS: Vessel wall thickening, permeability and inflammation were observed distally from the stenosis. They were eccentric and facing regions of normal wall thickness. Histological analysis confirmed eccentric plaque formation with lipid infiltration, intimal thickening and medial degradation. High phagocytic activity in the stenosis region was co-localized with high WSS, corresponding to intense medial degradation observed on histology samples. CONCLUSION: Lower WSS promotes atherosclerotic plaque development distal to an induced stenosis. Vascular and perivascular inflammation locations were predominant in the high WSS stenosis segment, where medial thinning was the major consequence.
Published: 2015
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27. Letter by Hope et al Regarding Article, 'Bicuspid Aortic Cusp Fusion Morphology Alters Aortic Three-Dimensional Outflow Patterns, Wall Shear Stress, and Expression of Aortopathy'

Author: Monica Sigovan, Michael D. Hope, Petter Dyverfeldt, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: medicine.medical_specialty, business.industry, Klinisk medicin, Hemodynamics, medicine.disease, Control subjects, Surgery, Bicuspid aortic valve, Physiology (medical), Internal medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, medicine, Shear stress, Cardiology, Cusp (anatomy), Outflow, In patient, Clinical Medicine, Cardiology and Cardiovascular Medicine, business
Abstract: We read with great interest the recent article by Dr Mahadevia and colleagues1 about altered systolic flow and aortopathy with bicuspid aortic valve (BAV) and the related editorial by Drs Uretsky and Gillam.2 We are pleased that the hemodynamic parameter of flow displacement performed well. It showed the clearest differences between patients with BAVs and control subjects and correlated with the pre-arch dilation seen in patients with right noncoronary leaflet fusion.1 Our experience with the parameter has been equally encouraging. It is easy to measure, shows excellent reproducibility, and appears to correlate well with aortic growth in initial application.3 We would like to point out, however, a technical difference between …
Published: 2014
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28. Photon counting spectral CT component analysis of coronary artery atherosclerotic plaque samples

Author: Gerhard Martens, Axel Thran, Monica Sigovan, Loic Boussel, Ewald Roessl, Philippe Douek, Philippe Coulon, Service de Radiologie [Hôpital de la Croix-Rousse - HCL], Hôpital de la Croix-Rousse [CHU - HCL], Hospices Civils de Lyon ( HCL ) -Hospices Civils de Lyon ( HCL ), 1 - Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales ( MOTIVATE ), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé ( CREATIS ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Hospices Civils de Lyon ( HCL ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Hospices Civils de Lyon ( HCL ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Philips Healthcare, Philips Research [Germany], Philips Research, Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Photon, Materials science, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Contrast Media, Coronary Artery Disease, Coronary artery disease, medicine, Humans, Scattering, Radiation, Radiology, Nuclear Medicine and imaging, [ SDV.IB.IMA ] Life Sciences [q-bio]/Bioengineering/Imaging, Photons, Full Paper, business.industry, Compton scattering, General Medicine, medicine.disease, Photon counting, Plaque, Atherosclerotic, Intensity (physics), Coronary arteries, medicine.anatomical_structure, Radiographic Image Interpretation, Computer-Assisted, Tomography, Autopsy, Nuclear medicine, business, Tomography, X-Ray Computed, Artery
Abstract: International audience; Objectives. To evaluate the capabilities of Photon Counting Spectral CT to differentiate components of coronary atherosclerotic plaque based on differences in spectral attenuation and iodine-based contrast agent concentration. Methods. 10 calcified and 13 lipid-rich atheromatous plaques from postmortem human coronary arteries were scanned with a Photon Counting Spectral CT scanner. Individual photons were counted and classified in one of 6 energy bins from 25 to 70 keV.Based on a maximum likelihood approach, maps of Photoelectric Absorption (PA), Compton Scattering (CS) and Iodine Concentration (IC) were reconstructed. Intensity measurements were performed on each map in the vessel wall, the surrounding perivascular fat, the lipid-rich and the calcified plaques. PA and CS values are expressed relative to pure water values. Comparison between these different elements was performed using Kruskal-Wallis tests with pairwise post-hoc Mann-Whitney U tests and Sidak p-values adjustment. Results. Results for vessel wall, surrounding perivascular fat, lipid-rich, and calcified plaques were respectively 1.19+/-0.09, 0.73+/-0.05, 1.08+/-0.14, 17.79+/-6.70 for PA; 0.96+/-0.02, 0.83+/-0.02, 0.91+/-0.03, 2.53+/-0.63 for CS, and 83.3+/-10.1, 37.6+/-8.1, 55.2+/-14.0, 4.9+/-20.0 mmol/l for IC, with significant differences between all tissues for PA, CS and IC (p
Published: 2014
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29. Systolic flow displacement correlates with future ascending aortic growth in patients with bicuspid aortic valves undergoing magnetic resonance surveillance

Author: Nicholas S. Burris, Elaine E. Tseng, Michael D. Hope, Heather A. Knauer, Monica Sigovan, and David Saloner
Subjects: Adult, Gadolinium DTPA, Male, medicine.medical_specialty, Adolescent, Heart Valve Diseases, Contrast Media, Phase contrast magnetic resonance imaging, Young Adult, Imaging, Three-Dimensional, Bicuspid Aortic Valve Disease, medicine.artery, Ascending aorta, medicine, Humans, Radiology, Nuclear Medicine and imaging, In patient, Displacement (orthopedic surgery), Aorta, Aged, Observer Variation, medicine.diagnostic_test, business.industry, Follow up studies, Hemodynamics, Magnetic resonance imaging, General Medicine, Blood flow, Organ Size, Middle Aged, Image Enhancement, Magnetic Resonance Imaging, Regional Blood Flow, Aortic Valve, cardiovascular system, Female, Radiology, business, Blood Flow Velocity, Follow-Up Studies
Abstract: Altered systolic blood flow in the ascending aorta has been correlated with increased aortic growth in patients with bicuspid aortic valves (BAVs). We used conventional, 2-dimensional (2D) phase contrast magnetic resonance imaging (PC-MRI) to assess the relationship between altered flow and future growth in patients with BAV.Aortic MRI data were reviewed for 17 adult patients with BAV with right-left leaflet fusion undergoing surveillance imaging who had 2D PC-MRI through their ascending aortas on an initial study, follow-up studies more than 1 year later, and an initial maximum aortic diameter of less than 4.5 cm. Diameters were measured at standard levels by 2 blinded reviewers. Normalized systolic flow displacement was calculated at peak systole from the PC-MRI data, and correlation with the interval aortic growth was performed, with adjustment for clinical/demographic factors.The average follow-up interval was 2.9 ± 1.3 years. Systolic flow displacement at the initial study strongly correlated with ascending aortic growth rate (r = 0.71, P0.005) with moderate, non-significant correlation between initial diameter and growth (r = 0.45, P = 0.214). Aortic growth was 4 times faster in patients with initial flow displacement of 0.2 or greater (n = 9) compared with those (n = 8) with initial flow displacement less than 0.2 (0.8 ± 0.4 vs 0.2 ± 0.3 mm/y; P = 0.002).Systolic flow displacement calculated from conventional 2D PC-MRI in the ascending aorta correlates with future aortic growth in patients undergoing routine surveillance imaging for BAV. With a cutoff valve of 0.2, flow displacement may be used to identify a subset of patients likely to have elevated growth rates and may better risk-stratify patients with BAV for aortic disease progression than vessel diameter alone.
Published: 2014

30. Ferumoxytol-enhanced magnetic resonance angiography is a feasible method for the clinical evaluation of lower extremity arterial disease

Author: Monica Sigovan, Emily V. Nosova, Christopher D. Owens, S. Marlene Grenon, Warren J. Gasper, Joseph H. Rapp, David Saloner, and Joy Walker
Subjects: Gadolinium DTPA, Male, medicine.medical_specialty, Renal function, Contrast Media, Pilot Projects, Kidney, Magnetic resonance angiography, Article, Coronary artery disease, Peripheral Arterial Disease, Predictive Value of Tests, Risk Factors, medicine, Humans, Prospective Studies, Renal Insufficiency, Prospective cohort study, Computed tomography angiography, Aged, medicine.diagnostic_test, business.industry, General Medicine, Middle Aged, medicine.disease, Ferrosoferric Oxide, Ferumoxytol, medicine.anatomical_structure, Lower Extremity, Feasibility Studies, Surgery, San Francisco, Radiology, Cardiology and Cardiovascular Medicine, business, Magnetic Resonance Angiography, Kidney disease, Glomerular Filtration Rate
Abstract: Background Renal toxicity from conventional, iodinated, intravenous contrast agents is a common complication in patients with peripheral artery disease (PAD). Similarly, the potential for serious side effects prevents the use of gadolinium-based agents in many patients with depressed renal function. Ferumoxytol-enhanced magnetic resonance angiography (Fe-MRA) is a novel technique that uses an intravenous, ultrasmall, superparamagnetic, iron oxide preparation, currently approved by the Food and Drug Administration for the treatment of iron deficiency anemia in adults with chronic kidney disease. Our objective was to determine the feasibility of Fe-MRA for clinical decision making in PAD patients. Methods This was a prospective pilot study assessing 10 patients with suspected arterial occlusive disease with contrast-enhanced MRA of the aorta and lower extremities. Of those, 5 had renal insufficiency and were imaged with Fe-MRA, whereas the remainder underwent gadolinium-enhanced MRA. Qualitative and quantitative evaluations of deidentified images at each arterial station were independently performed by 4 blinded vascular surgeons. Results All patients were men, with an average age of 68 ± 4 years. The 2 groups had similar incidences of diabetes, hypertension, hyperlipidemia, and coronary artery disease. Patients undergoing Fe-MRA had significantly decreased renal function (estimated glomerular filtration rate, 35.4 vs. 77.6; P = 0.02). There were no adverse events during contrast administration in either group. No difference was found in the overall quality of the ferumoxytol versus the gadolinium studies (7.1 ± 2.0 vs. 7.4 ± 2.4, P = 0.67). Similarly, reviewers felt comfortable basing clinical decisions on the images 89% of the time with both the ferumoxytol and gadolinium groups (P = 1.00). Conclusions This is the first report of an important alternative to conventional computed tomography angiography and MRA in PAD patients, particularly in the setting of renal insufficiency. Fe-MRA provides a useful tool in patients with suspected lower extremity PAD without the potential risks of gadolinium.
Published: 2014

31. High-Resolution MRI Visualization of Aneurysmal Thrombosis after Flow Diverter Stent Placement

Author: Monica Sigovan, Guy Courbebaisse, Benjamin Gory, Francis Turjman, Carolina Vallecilla, Department of Interventional Neuroradiology, Hôpital neurologique et neurochirurgical Pierre Wertheimer [CHU - HCL], Hospices Civils de Lyon ( HCL ) -Hospices Civils de Lyon ( HCL ), 1 - Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales ( MOTIVATE ), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé ( CREATIS ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Hospices Civils de Lyon ( HCL ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Hospices Civils de Lyon ( HCL ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: medicine.medical_specialty, Flow diverter stent, genetic structures, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, High resolution, Sensitivity and Specificity, Aneurysm, Occlusion, medicine, Humans, Radiology, Nuclear Medicine and imaging, Treatment Failure, cardiovascular diseases, Thrombus, [ SDV.IB.IMA ] Life Sciences [q-bio]/Bioengineering/Imaging, medicine.diagnostic_test, business.industry, Reproducibility of Results, Magnetic resonance imaging, Intracranial Aneurysm, Middle Aged, medicine.disease, Image Enhancement, equipment and supplies, Thrombosis, Magnetic Resonance Imaging, medicine.anatomical_structure, Fundus (uterus), cardiovascular system, Female, Stents, Neurology (clinical), Radiology, Intracranial Thrombosis, business
Abstract: International audience; Flow-diverter stents are the new promising tools in the treatment of intracranial aneurysms allowing progressive aneurysm occlusion. Here, we report a case where high-resolution magnetic resonance imaging showed thrombus at fundus of the aneurysm sac, indicating a progressive intraaneurysmal thrombosis after flow-diverter placement.
Published: 2014
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32. Vascular remodeling in autogenous arterio-venous fistulas by MRI and CFD

Author: Christopher D. Owens, Monica Sigovan, Warren J. Gasper, David Saloner, Vitaliy L. Rayz, Hugh F. Alley, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, Kidney Disease, Fistula, Pulsatile flow, Hemodynamics, Computational fluid dynamics, Medical and Health Sciences, Magnetic resonance angiography, Imaging, Postoperative Complications, Engineering, Surgical, 80 and over, Medicine, Vascular remodeling, Aged, 80 and over, medicine.diagnostic_test, Arteriovenous Shunt, Patient specific, Middle Aged, medicine.anatomical_structure, Hemodialysis fistula, Arm, Biomedical Imaging, Radiology, Artery, medicine.medical_specialty, Biomedical Engineering, Bioengineering, Anastomosis, Article, Arteriovenous Shunt, Surgical, Imaging, Three-Dimensional, Magnetic resonance imaging, Renal Dialysis, Clinical Research, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Humans, cardiovascular diseases, Aged, business.industry, WSS, medicine.disease, Three-Dimensional, Hydrodynamics, Vascular access, business, Magnetic Resonance Angiography
Abstract: Hemodynamic parameters play an important role in regulating vascular remodeling in arterio-venous fistula (AVF) maturation. Investigating the changes in hemodynamic parameters during AVF maturation is expected to improve our understanding of fistula failure, but very little data on actual temporal changes in human AVFs is available. The present study aimed to assess the feasibility of using a noncontrast-enhanced MRI protocol combined with CFD modeling to relate hemodynamic changes to vascular remodeling following native AVF placement. MR angiography (MRA) and MR velocimetry (MRV) data was acquired peri-operatively, 1 month, and 3 months later in three patients. Vascular geometries were obtained by segmentation of the MRA images. Pulsatile flow simulations were performed in the patient specific vascular geometries with time-dependent boundary conditions prescribed from MRV measurements. A principal result of the study is the description of WSS changes over time in the same patients. The disturbed flow observed in the venous segments resulted in a variability of the WSS distribution and could be responsible for the non-uniform remodeling of the vessel. The artery did not show regions of disturbed flow upstream from the anastomosis, which would be consistent with the uniform remodeling. MRI use demonstrated the ability to provide a comprehensive evaluation of clinically relevant information for the investigation of upper extremity AVFs. 3D geometry from MRA in combination with MRV provides the opportunity to perform detailed CFD analysis of local hemodynamics in order to determine flow descriptors affecting fistula maturation.
Published: 2013

33. USPIO-enhanced MR Angiography of Arteriovenous Fistulas in Patients with Renal Failure

Author: Hugh F. Alley, Warren J. Gasper, Monica Sigovan, David Saloner, Christopher D. Owens, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)
Subjects: Male, medicine.medical_specialty, Kidney Disease, Anastomosis, medicine.medical_treatment, Contrast Media, Medical and Health Sciences, Sensitivity and Specificity, Magnetite Nanoparticles, Text mining, Clinical Research, Surgical, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, medicine, Humans, Radiology, Nuclear Medicine and imaging, In patient, Renal Insufficiency, Original Research, business.industry, Arteriovenous Anastomosis, Anastomosis, Surgical, Mr angiography, Reproducibility of Results, Dextrans, Image Enhancement, Nuclear Medicine & Medical Imaging, Biomedical Imaging, Female, Radiology, Hemodialysis, business, Magnetic Resonance Angiography
Abstract: PurposeTo determine the feasibility of using ferumoxytol-enhanced magnetic resonance (MR) angiography to depict the vasculature of hemodialysis fistulas and improve image quality compared with nonenhanced time-of-flight (TOF) MR angiography.Materials and methodsThe study was institutional review board approved and was in compliance with HIPAA regulations. All participants provided written informed consent. TOF and first-pass ferumoxytol-enhanced MR angiography were performed in 10 patients with upper extremity autogenous fistulas. Ferumoxytol was administered as a bolus solution containing 430 μmol of elemental iron. A qualitative comparison was performed on maximum intensity projection images. Lumen depiction was evaluated by using a five-point scale. The uniformity of intraluminal signal intensity was measured as the ratio between the mean signal intensity of the entirety of the imaged fistula and its standard deviation. The contrast-to-noise ratio (CNR) between intraluminal signal and adjacent tissue was evaluated as a function of image acquisition time. Lumen depiction scores, luminal signal heterogeneity, and CNR efficiency were compared between TOF and ferumoxytol-enhanced MR angiography by using a Wilcoxon-Mann-Whitney test.ResultsFlow artifacts were greatly reduced by the use of ferumoxytol-enhanced MR angiography. Ferumoxytol-enhanced MR angiography had significantly better performance than TOF MR angiography as measured with the following: lumen depiction scores in all segments (mean, 4.7±0.1 [standard error of the mean]; vs 3.0±0.3 for arterial inflow, 4.1±0.3 vs 1.9±0.3 for arterial outflow, 3.7±0.3 vs 1.8±0.2 for anastomosis, and 4.5±0.2 vs 2.1±0.2 for venous outflow; P
Published: 2012

34. Anti-inflammatory drug evaluation in ApoE-/- mice by ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance imaging

Author: Zouher Majd, Magali Breisse, Eric Lancelot, Monica Sigovan, Claire Corot, Nicolas Provost, Elena A. Kaye, Emmanuelle Canet-Soulas, Sigovan, Monica, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche et d'Application en Traitement de l'Image et du Signal (CREATIS), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National de la Recherche Agronomique (INRA)
Subjects: Pathology, medicine.medical_specialty, Angiotensin receptor, Apolipoprotein B, Arteriosclerosis, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, Contrast Media, Tetrazoles, 030204 cardiovascular system & hematology, 030218 nuclear medicine & medical imaging, Renin-Angiotensin System, 03 medical and health sciences, chemistry.chemical_compound, Mice, 0302 clinical medicine, Irbesartan, Apolipoproteins E, In vivo, medicine.artery, medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Animals, Radiology, Nuclear Medicine and imaging, Longitudinal Studies, Magnetite Nanoparticles, 2. Zero hunger, Aorta, medicine.diagnostic_test, biology, Cholesterol, business.industry, Macrophages, Biphenyl Compounds, Antagonist, Magnetic resonance imaging, General Medicine, Magnetic Resonance Imaging, 3. Good health, Disease Models, Animal, chemistry, biology.protein, Disease Progression, Female, business, Angiotensin II Type 1 Receptor Blockers, medicine.drug
Abstract: Objectives: The renin-angiotensin system and local phagocytic activity play a major role in atherosclerotic plaque development. Treatment with irbesartan, an antagonist of angiotensin II receptor, can decrease atherosclerotic lesion formation. Iron oxideYenhanced magnetic resonance imaging (MRI) can be successfully used to evaluate the phagocytic activity in the atherosclerotic plaque in mice. In this study, we used 2 iron oxideYenhanced MRI strategies, in vivo labeling by injection of iron oxide particles and injection of in vitro labeled macrophages, to investigate the effect of irbesartan on both atherosclerotic plaque size and macrophage content in apolipoprotein (Apo) EYdeficient mice. Materials and Methods: ApoEj/j female mice (C57BL/6 background; Charles-River, France) were divided into 2 groups (irbesartan treated [TG] or not treated [NTG]) and started on a high-fat diet (Harlan TD88137 Western Diet, 21% fat, 0.2% cholesterol). Animals underwent magnetic resonance examinations on a 7-T scanner at baseline and at 14 and 28 weeks of treatment. At each time point, 2 MRI sessions were performed, before and 48 hours after administration of an iron oxide agent (P904; Guerbet, France) or magnetically labeled macrophages (M&). At the end of the follow-up, blood samples were taken for plasma lipid dosing and aorta samples for histology. The study was approved by the animal experimentation ethic committee of our institution. Vessel wall area measurements were performed on high-resolution spin echo transverse images. Multiecho gradient echo images acquired with the same geometry were used to calculate T2* maps of the vessel wall using a pixel-by-pixel monoexponential fit. Irbesartan effect on vessel wall area over time was assessed using a factorial analysis of variance test. T2* values of the vessel wall at preY and postYultrasmall superparamagnetic iron oxide (USPIO) administration were analyzed with a 1-way analysis of variance test with Bonferroni post hoc. Results: Irbesartan treatment resulted in significantly smaller vessel wall areas at 28 weeks of treatment (P = 0.04). Postinjection values varied significantly over time for both the NTG-P904 (P = 0.02) and the TG-P904 (P = 0.01) groups. Furthermore, when comparing the TG-P904 with the NTGP904 group at 28 weeks of treatment, a significant difference was obtained for both preY and postYUSPIO administration values (P = 0.01). In the labeledmacrophage group, postinjection T2* values were smaller than the preinjection ones for the NTG animals at 14 weeks of treatment. No T2* changes were observed in the TG-M? group. The difference between preY and postYUSPIO administration T2* values ($T2*) was significantly smaller in the TG-P904 group compared with the NTG-P904 group at 28 weeks of treatment. At this point, a good correlation (R =0 .7,P = 0.03) was found between the $T2* values in the P904 imaging group and the macrophage-covered area by immunohistological analysis. Conclusions: The present study illustrates an MRI follow-up of intraplaque macrophages using in vivo labeling by iron oxide particle injection and macrophage injection after in vitro USPIO labeling in the assessment of a therapeutic effect in a mouse model of atherosclerosis. Even though in vivo labeling is not fully specific of macrophage uptake, it enabled the detection of a treatment-related reduction in the macrophage content of atherosclerotic plaques in ApoEj/j mice.
Published: 2012

35. In vivo cardiac anatomical and functional effects of wheel running in mice by magnetic resonance imaging

Author: Emeline Aufradet, Hasan Alsaid, Florian Schäfer, Monica Sigovan, Cyril Martin, Erica N. Chirico, Amine Bessaad, Geneviève De Souza, Emmanuelle Canet-Soulas, Centre de Recherche et d'Application en Traitement de l'Image et du Signal (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), LENS, University of Fiorentino, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UR226, Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National de la Recherche Agronomique (INRA), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)
Subjects: Male, Pathology, medicine.medical_specialty, Gating, 030204 cardiovascular system & hematology, Left ventricular hypertrophy, General Biochemistry, Genetics and Molecular Biology, Pathogenesis, 03 medical and health sciences, Mice, 0302 clinical medicine, In vivo, Internal medicine, Physical Conditioning, Animal, Image Processing, Computer-Assisted, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Medicine, Aerobic exercise, Animals, Muscle, Skeletal, medicine.diagnostic_test, business.industry, Magnetic resonance imaging, Cardiorespiratory fitness, Heart, medicine.disease, Magnetic Resonance Imaging, Mice, Inbred C57BL, Wheel running, Cardiology, business, 030217 neurology & neurosurgery
Abstract: Physical activity is frequently used as a strategy to decrease pathogenesis and improve outcomes in chronic pathologies such as metabolic or cardiac diseases. In mice, it has been shown that voluntary wheel running (VWR) could induce an aerobic training effect and may provide a means of exploring the relationship between physical activity and the progression of pathology, or the effect of a drug on locomotor activity. To the best of our knowledge, in vivo magnetic resonance imaging (MRI) and other non-invasive methods had not been investigated for training evaluation in mice; therefore, it was proposed to test an MRI method coupled with a cardiorespiratory gating system on C57Bl/6 mice for in vivo heart anatomical and functional characterization in both trained and untrained animals. Twenty mice were either assigned to a 12-week VWR program or to a control group (CON – no wheel in the cage). At week 12, MRI scans showed an increase in the left ventricular (LV) wall mass in the VWR group compared with the CON group. The ex vivo measurements also found an increase in the heart and LV weight, as well as an increase in oxidative enzyme activities (i.e. cytochrome c oxidase [COx] in the soleus). In addition, correlations have been observed between ex vivo LV/body weight ratio, COx activity in the soleus and in vivo MRI LV wall mass/body weight. In conclusion, mouse cardiac MRI methods coupled with a cardio-respiratory gating system are sufficiently effective and feasible for non-invasive, training-induced heart hypertrophy characterization, and may be used for longitudinal training level follow-up in mouse models of cardiovascular and metabolic diseases.
Published: 2012
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36. Comparison of four-dimensional flow parameters for quantification of flow eccentricity in the ascending aorta

Author: David Saloner, Monica Sigovan, Michael D. Hope, Petter Dyverfeldt, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Adult, Male, medicine.medical_specialty, Adolescent, Systole, media_common.quotation_subject, Flow angle, Contrast Media, Magnetic Resonance Imaging, Cine, Aorta, Thoracic, Cardiovascular System, Imaging, Three-Dimensional, medicine.artery, Ascending aorta, medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Image Processing, Computer-Assisted, Thoracic aorta, Eccentric, Humans, Radiology, Nuclear Medicine and imaging, Computer Simulation, Eccentricity (behavior), Aorta, media_common, Mathematics, Models, Statistical, Blood flow, Anatomy, Magnetic Resonance Imaging, Surgery, Flow (mathematics), Female
Abstract: To compare quantitative parameters for assessing the degree of eccentric systolic blood flow in the ascending thoracic aorta (AsAo).Forty-one patients were studied with three-dimensional (3D), cine phase-contract MRI (4D Flow). Analysis was performed at peak systole for a cross-sectional plane in the AsAo just distal to the sinotubular junction. AsAo flow was graded as normal, mildly, or markedly eccentric based on qualitative visual assessment. For quantitative analysis, flow jet angle and normalized flow displacement from the vessel center were calculated.Patients with normal AsAo systolic flow (n = 25) had an average flow jet angle of 13.7 degrees and flow displacement 0.04. These parameters were significantly elevated for patients with mild eccentric systolic flow (n = 6): 24.6 degrees (P = 0.012) and 0.12 (P = 0.001), respectively. However, for patients with marked eccentric flow (n = 10), only flow displacement was significantly elevated compared with the mild eccentric group (0.18; P = 0.04); flow angle was 25.7 degrees.Flow displacement is a more reliable quantitative parameter for measuring eccentric AsAo systolic flow than flow jet angle, and should be evaluated in studies investigating the role of eccentric flow in the promotion of aortic pathology.
Published: 2011

37. Quantification of iron-labeled cells with positive contrast in mouse brains

Author: Yves Berthezène, Emmanuelle Canet-Soulas, Jérôme Honnorat, Virginie Desestret, Monica Sigovan, Emilie Devillard, Monique Touret, Marlène Wiart, Serge Nataf, Adrien Riou, Norbert Nighoghossian, Fabien Chauveau, and Jean-Christophe Brisset
Subjects: Cancer Research, Relaxometry, medicine.medical_specialty, Iron, Contrast Media, Ferric Compounds, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, Mice, 0302 clinical medicine, Nuclear magnetic resonance, Text mining, medicine, Image Processing, Computer-Assisted, Animals, Radiology, Nuclear Medicine and imaging, medicine.diagnostic_test, Staining and Labeling, Chemistry, business.industry, Brain, Magnetic resonance imaging, equipment and supplies, Mice, Inbred C57BL, Oncology, Positive contrast, Nanoparticles, Female, Radiology, business, Artifacts, human activities, 030217 neurology & neurosurgery
Abstract: To quantify small amounts of iron-labeled cells in mouse brains with magnetic resonance imaging (MRI).Iron-labeled cells (from 500 to 7,500) were stereotaxically transplanted into the brain of living mice that were subsequently imaged with MRI at 4.7 T. We compared four quantitative methods: (1) T2 relaxometry, (2) T2* relaxometry, (3) the volume of the cloverleaf hypointense artifact generated on T2*-weighted images, and (4) the volume of the cloverleaf hyperintense artifact generated on positive contrast images.The methods based on relaxometry, whether T2 or T2*, did not correlate with the number of injected cells. By contrast, those based on measurement of cloverleaf artifact volume, whether using negative or positive enhancement, showed a significant linear relationship for the given range of cells (R [0.92-0.95], p 0.05).T2* artifact volume imaging (negative or positive) appears promising for the quantification of magnetically labeled cells following focal injection in the brain.
Published: 2010

38. Assessment of age modulated vascular inflammation in ApoE-/- mice by USPIO-enhanced magnetic resonance imaging

Author: Claire Corot, Eric Lancelot, Monica Sigovan, Bruno Neyran, Emmanuelle Canet-Soulas, Nicolas Provost, Zouher Majd, Hasan Alsaid, Amine Bessaad, Magali Breisse, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre de Recherche et d'Application en Traitement de l'Image et du Signal (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National de la Recherche Agronomique (INRA), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL), and Sigovan, Monica
Subjects: Apolipoprotein E, Pathology, medicine.medical_specialty, Arteriosclerosis, Statistics as Topic, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, Inflammation, 030204 cardiovascular system & hematology, Risk Assessment, 030218 nuclear medicine & medical imaging, Mice, 03 medical and health sciences, Apolipoproteins E, 0302 clinical medicine, Image Processing, Computer-Assisted, medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Animals, Radiology, Nuclear Medicine and imaging, Correlation test, Aorta, Rupture, Analysis of Variance, medicine.diagnostic_test, Apoe mice, Vascular inflammation, business.industry, Macrophages, Age Factors, Thrombosis, Magnetic resonance imaging, General Medicine, medicine.disease, Magnetic Resonance Imaging, Mice, Inbred C57BL, Disease Progression, Feasibility Studies, Analysis of variance, medicine.symptom, Nuclear medicine, business, Software
Abstract: Objective: Inflammation within atherosclerotic lesions increases the risk for plaque rupture and thrombosis. A functional approach to plaque analysis is the intravenous administration of ultrasmall superparamagnetic particles of iron oxide (USPIO) that enables visualization of macrophages residing in the plaques. In this study, we sought to characterize the age-related inflammatory status associated with atherosclerosis lesion progression in ApoE ―/― mice using USPIO-enhanced magnetic resonance imaging (MRI). Materials and Methods: A total of 24 ApoE ―/― mice were divided in 4 groups (N = 6) and were given a high cholesterol diet from 6 weeks of age to the end of the protocol. One group per MR time point was investigated at 10, 16, 24, and 34 weeks of age. Each MR examination was performed on a 4.7 T scanner and consisted of baseline and 48 hours post-USPIO administration imaging sessions. P904, a USPIO contrast agent (Guerbet, Paris, France) with a potential for plaque macrophage targeting, was used. Vessel wall area measurements were performed on high resolution spin echo transverse images. Multi-echo gradient-echo images acquired with the same geometry were used to calculate T2 * maps of the vessel wall using a pixel-by-pixel monoexponential fit. A one-way analysis of variance was performed to characterize the temporal variation of vessel wall area, susceptibility artifact area, baseline, and post-USPIO T2 * values. MR measurements were correlated with the histologic findings. Results: A significant increase was found in the aortic wall area from 1.4 ± 0.2 at 10 weeks to 2.0 ± 0.3 mm 2 at 34 weeks of age (P < 0.05). Concerning the post-USPIO MRI, signal loss regions, with patterns spanning from focal to the complete disappearance of the vessel wall, were observed on all postcontrast images. A significant increase in the size of the susceptibility artifact was observed from 0.5 ± 0.2 to 2.4 ± 1.0 at 24 weeks (P < 0.05) and to 2.0 ± 0.9 mm 2 at 34 weeks (P < 0.05). The T2 * values calculated on the 48 hours post-USPIO images were shorter compared with baseline. The decrease was 34% ± 16% at 10 weeks, 57% ± 11% at 16 weeks, 57% ± 16% at 24 weeks, and 48% ± 13% at 34 weeks. The Pearson's correlation test between measurement of aortic wall area performed on both MR images and histologic analysis showed a statistically significant correlation (r = 0.695 and P < 0.05). A correlation was also obtained between the signal loss area and the macrophages covered area (r = 0.68 and P < 0.05). Conclusions: This study demonstrated the feasibility of USPIO-enhanced MRI in assessing the inflammatory status related to the temporal progression of the atherosclerosis plaque in ApoE ―/― transgenic mice model of atherosclerosis. In our experimental conditions, the vascular inflammation peak, for the ApoE ―/― mice feeding high-fat/high-cholesterol diet is measured between 16 and 24 weeks of age.
Published: 2010

39. Rapid-clearance iron nanoparticles for inflammation imaging of atherosclerotic plaque: initial experience in animal model

Author: Xavier Violas, Danielle Ibarrola, Eric Lancelot, Christine Laclédère, Catherine Desbleds-Mansard, Philippe Douek, Hasan Alsaid, Claire Corot, Jean-Sebastian Raynaud, D. Gamondes, Loic Boussel, Véronique Vives, Dominique Sappey-Marinier, Emmanuelle Canet-Soulas, Monica Sigovan, Abdulrazzaq Sulaiman, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche et d'Application en Traitement de l'Image et du Signal (CREATIS), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etude et de Recherche Multimodal Et Pluridisciplinaire en imagerie du vivant (CERMEP - imagerie du vivant), Université de Lyon-Université de Lyon-CHU Grenoble-Hospices Civils de Lyon (HCL)-CHU Saint-Etienne-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Groupe Hospitalier Est, Service de Radiologie, Hospices Civils de Lyon (HCL), Service de Radiologie, Hôpital Louis Pradel [CHU - HCL], Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National de la Recherche Agronomique (INRA), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Exploration et de Recherche Médicales par Émission de Positons (CERMEP), Université Joseph Fourier - Grenoble 1 (UJF)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-CHU Grenoble-Hospices Civils de Lyon (HCL)-CHU Saint-Etienne-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL)
Subjects: Pathology, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Contrast Media, Pilot Projects, 030204 cardiovascular system & hematology, 030218 nuclear medicine & medical imaging, 0302 clinical medicine, Magnetite Nanoparticles, ComputingMilieux_MISCELLANEOUS, Dextrans, Oxides, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], [PHYS.PHYS.PHYS-MED-PH]Physics [physics]/Physics [physics]/Medical Physics [physics.med-ph], [SDV.IB]Life Sciences [q-bio]/Bioengineering, Rabbits, medicine.symptom, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, medicine.medical_specialty, Metabolic Clearance Rate, Iron, Inflammation, [SDV.IB.MN]Life Sciences [q-bio]/Bioengineering/Nuclear medicine, Sensitivity and Specificity, 03 medical and health sciences, Animal model, [SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system, Inflammation imaging, Metabolic clearance rate, medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Animals, Humans, Radiology, Nuclear Medicine and imaging, [SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], Aortitis, business.industry, Vascular disease, Reproducibility of Results, medicine.disease, Atherosclerosis, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Ferrosoferric Oxide, Disease Models, Animal, Rabbit model, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, business, Magnetic Resonance Angiography, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract: To evaluate the use of a recently developed fast-clearing ultrasmall superparamagnetic iron oxide (USPIO) for detection of vascular inflammation in atherosclerotic plaque.The study protocol was approved by the animal experimentation ethics committee. A recently introduced USPIO, P904, and a reference-standard USPIO, ferumoxtran-10, were tested in a rabbit model of induced aortic atherosclerosis. In vivo magnetic resonance (MR) angiography and T2*-weighted plaque MR imaging were performed at baseline and after administration of P904 and ferumoxtran-10 (administered dose for both, 1000 micromol of iron per kilogram of body weight) in 26 hyperlipidemic New Zealand white rabbits. The variation in vessel wall area over time was evaluated with nonparametric testing. Ex vivo MR imaging findings were compared with iron content at linear regression analysis.With in vivo MR imaging, plaque analysis was possible as early as 24 hours after P904 injection. The authors observed a 27.75% increase in vessel wall area due to susceptibility artifacts on day 2 (P = .04) and a 38.81% increase on day 3 (P = .04) after P904 administration compared with a 44.5% increase in vessel wall area on day 7 (P = .04) and a 34.8% increase on day 10 (P = .22) after ferumoxtran-10 administration. These susceptibility artifacts were correlated with intraplaque iron uptake in the corresponding histologic slices. The number of pixels with signal loss on the ex vivo MR images was linearly correlated with the logarithm of the iron concentration (P = .0001; R(2) = 0.93).Plaque inflammation in rabbits can be detected earlier with P904 than with ferumoxtran-10 owing to the faster blood pharmacokinetics and the early uptake of P904 in the reticuloendothelial system.http://radiology.rsnajnls.org/cgi/content/full/252/2/401/DC1.
Published: 2009
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40. Modified electrocardiograph-triggered black-blood turbo spin-echo technique to improve T1-weighting in contrast-enhanced MRI of atherosclerotic carotid arteries

Author: Romaric Loffroy, Gwenael Herigault, Emmanuelle Canet-Soulas, Monica Sigovan, Philippe Douek, Loic Boussel, Sigovan, Monica, Imagerie et modélisation Vasculaires, Thoraciques et Cérébrales (MOTIVATE), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de radiologie et d'Imagerie médicale diagnostique et thérapeutique (CHU de Dijon), Centre Hospitalier Universitaire de Dijon - Hôpital François Mitterrand (CHU Dijon), Laboratoire Electronique, Informatique et Image [UMR6306] (Le2i), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Arts et Métiers (ENSAM), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de Radiologie, Hôpital Louis Pradel [CHU - HCL], Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Bourgogne (UB)-École Nationale Supérieure d'Arts et Métiers (ENSAM), HESAM Université (HESAM)-HESAM Université (HESAM)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL)
Subjects: Carotid Artery Diseases, Male, CONTRAST ENHANCED MRI, Image quality, Carotid arteries, media_common.quotation_subject, Black blood, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, Contrast Media, 030218 nuclear medicine & medical imaging, Electrocardiography, 03 medical and health sciences, Meglumine, 0302 clinical medicine, Image Interpretation, Computer-Assisted, Organometallic Compounds, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Humans, Contrast (vision), Medicine, Radiology, Nuclear Medicine and imaging, Aged, media_common, Pulse (signal processing), business.industry, Middle Aged, Fast spin echo, Magnetic Resonance Imaging, Weighting, Female, Artifacts, business, Nuclear medicine, 030217 neurology & neurosurgery
Abstract: Purpose To assess the efficacy of a modified electrocardiograph (EKG)-triggered black-blood T1W (T1W) spin-echo sequence in improving contrast on post-gadolinium high-resolution carotid plaque imaging by implementing heart-rate–independent contrast preparation. Materials and Methods We used a standard EKG-triggered double inversion-recovery (DIR) turbo spin-echo (TSE) sequence modified with the addition of an extra saturation (90°) radio frequency (RF) pulse placed immediately after the DIR module, shortening the repetition time to a fixed value of 400 msec. A total of 10 patients with atherosclerotic disease were included in the study. Postinjection intraplaque contrast measurements were performed on each patient for the standard and the modified sequence. Results Post-gadolinium-injection intraplaque contrast was 31.7 ± 12.8% with the standard T1W sequence (nT1-TSE), and 45.3 ± 17.2% with the modified T1W sequence (mT1-TSE), showing a significant contrast enhancement of 13.6% (P < 0.001) without significant image quality modification. Conclusion The addition of a RF pulse to the standard EKG-triggered T1W TSE sequence increased intraplaque contrast without increasing sequence acquisition time. Furthermore, it appeared to be a robust technique, easy to implement on clinical scanners. J. Magn. Reson. Imaging 2008;28:533–537. © 2008 Wiley-Liss, Inc.
Published: 2008

41. Imaging Biomarkers of Aortic Disease

Author: Michael D. Hope, David Saloner, Monica Sigovan, Elyse Foster, Jarrett Wrenn, and Elaine E. Tseng
Subjects: medicine.medical_specialty, medicine.diagnostic_test, business.industry, Follow up studies, Hemodynamics, medicine.disease, Aortic disease, Magnetic resonance angiography, Aortic wall, Bicuspid aortic valve, Internal medicine, cardiovascular system, medicine, Cardiology, Eccentric, Cardiology and Cardiovascular Medicine, business, Aortic dilation
Abstract: To the Editor: Is the aortic dilation that is commonly seen with bicuspid aortic valve (BAV) related to intrinsic aortic wall fragility or altered systolic hemodynamics? Recent publications on the topic favor the intrinsic fragility hypothesis. But recent advancements in imaging show very abnormal
Published: 2012
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42. Development of a Rapid, High Resolution Magnetic Resonance Imaging Protocol for the Assessment of Arteriovenous Fistula Remodeling

Author: Christopher D. Owens, Monica Sigovan, David Saloner, Joseph H. Rapp, Warren J. Gasper, and Vitalliy Rayz
Subjects: Protocol (science), medicine.medical_specialty, medicine.diagnostic_test, business.industry, medicine, High resolution, Arteriovenous fistula, Magnetic resonance imaging, Surgery, Radiology, medicine.disease, business, Cardiology and Cardiovascular Medicine
Published: 2011
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43. A New Carotid 3D MRI Sequence for Stenosis Measurement and Plaque Characterization at the Same Time

Author: Monica Sigovan, P. Douek, S. Bros, Antoine Millon, Z. Fayad, P.M. Robson, and L. Boussel
Subjects: Medicine(all), Stenosis, business.industry, medicine, Surgery, Cardiology and Cardiovascular Medicine, Nuclear medicine, business, medicine.disease, Sequence (medicine)
Published: 2014
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44. Lower wss drives intimal thickening, but high wss gradients and inflammation are responsible of stenosis medial thinning

Author: Monica Sigovan, N. Provost, David Patsouris, C. Paquet, E. Canet Soulas, Loic Boussel, André Sérusclat, Z. Majd, J.L. Mathevet, V. Louzier, A. Millon, and Alain Géloën
Subjects: medicine.medical_specialty, Stenosis, Thinning, business.industry, Internal medicine, medicine, Cardiology, Inflammation, Thickening, medicine.symptom, Cardiology and Cardiovascular Medicine, medicine.disease, business
Published: 2014
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45. CMR2009: 10.05: Assessment of age modulated vascular inflammation in ApoEâ/âmice by USPIO-enhanced MRI

Author: Monica Sigovan, M. Breisse, B. Neyran, Emmanuelle Canet-Soulas, Hasan Alsaid, Claire Corot, Z. Majd, N. Provost, and Amine Bessaad
Subjects: Pathology, medicine.medical_specialty, Apoe mice, Vascular inflammation, business.industry, Medicine, Radiology, Nuclear Medicine and imaging, business
Published: 2009
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46. CMR 2007: 1.04:In-vivo USPIO's follow-up and optimized MRI protocol for inflammation imaging in atherosclerotic plaques

Author: C. Desbleds-Mansard, Philippe Douek, Monica Sigovan, Emmanuelle Canet-Soulas, Claire Corot, Jean-Sébastien Raynaud, Loic Boussel, D. Ibarrola, Xavier Violas, D. Gamondes, Eric Lancelot, Dominique Sappey-Marinier, and A. Sulaiman
Subjects: Pathology, medicine.medical_specialty, In vivo, business.industry, Inflammation imaging, medicine, Radiology, Nuclear Medicine and imaging, business
Published: 2007
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47. Improved quantification of abnormal aortic flow in 3D compared to standard 2D approach

Author: Michael D. Hope, Petter Dyverfeldt, Jarrett Wrenn, David Saloner, and Monica Sigovan
Subjects: Aortic valve disease, Medicine(all), medicine.medical_specialty, lcsh:Diseases of the circulatory (Cardiovascular) system, Radiological and Ultrasound Technology, business.industry, Aortic flow, medicine.disease, Bioinformatics, Text mining, Bicuspid aortic valve, lcsh:RC666-701, Internal medicine, Poster Presentation, medicine, Cardiology, cardiovascular system, Radiology, Nuclear Medicine and imaging, Cardiology and Cardiovascular Medicine, business, Angiology
Abstract: Author(s): Sigovan, Monica; Hope, Michael D; Wrenn, Jarrett; Dyverfeldt, Petter; Saloner, David
Published: 2013

48. Reproducibility of quantitative analysis of aortic 4D flow data

Author: David Saloner, Monica Sigovan, Petter Dyverfeldt, Jarrett Wrenn, and Michael D. Hope
Subjects: Medicine(all), lcsh:Diseases of the circulatory (Cardiovascular) system, Reproducibility, medicine.medical_specialty, Radiological and Ultrasound Technology, business.industry, Hemodynamics, Blood flow, computer.software_genre, Flow (mathematics), lcsh:RC666-701, Poster Presentation, cardiovascular system, Shear stress, Medicine, Radiology, Nuclear Medicine and imaging, Data mining, Cardiology and Cardiovascular Medicine, business, Quantitative analysis (chemistry), Displacement (fluid), computer, Biomedical engineering, Angiology
Abstract: Background 3D cine phase-contrast CMR ("4D Flow”) permits quantitative assessment of anomalous alterations of aortic blood flow. Two hemodynamic parameters that have been used for this purpose is the wall shear stress (WSS), which is known to regulate endothelial cell function, and the normalized flow displacement from the vessel center, which was recently shown to correlate with increased growth rates of ascending aortic dilation [1,2]. Analysis of these hemodynamic parameters requires that a user 1) positions a 2D plane of interest in the volumetric 4D Flow dataset and 2) delineates the contour of the vascular lumen in this 2D plane. We set out to assess the reproducibility of 4D Flow-based estimation of WSS and normalized flow displacement at these two critical levels of user-interaction. Furthermore, we assessed which of the parameters correlate best with aortic growth.
Published: 2013

49. MS360 ANTI-ANGIOTENSIN DRUG EVALUATION IN apoE−/− MICE BY USPIO-ENHANCED MRI AT 7 T

Author: C. Corot, Monica Sigovan, N. Provost, E. Kaye, Emmanuelle Canet-Soulas, M. Breisse, Z. Majd, Amine Bessaad, and E. Lancelot
Subjects: Drug, Apoe mice, business.industry, media_common.quotation_subject, Renin–angiotensin system, Internal Medicine, Medicine, General Medicine, Pharmacology, Cardiology and Cardiovascular Medicine, business, media_common
Published: 2010
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